Journal articles: 'Long Column'

1

Shahu, J. T., and Y. R. Reddy. "Estimating long-term settlement of floating stone column groups." Canadian Geotechnical Journal 51, no. 7 (July 2014): 770–81. http://dx.doi.org/10.1139/cgj-2012-0477.

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Design charts for estimating long-term drained settlement of floating stone column group foundations are presented based on three-dimensional, elastoplastic, finite element analyses. In the analyses, the soft soil behavior is represented by the modified Cam-clay model while the stone column and mat are represented by the Mohr–Coulomb model. The finite element predictions are calibrated against model test results. A detailed parametric study of prototype stone column group foundations of various configurations is carried out to evaluate the relative importance of various foundation parameters on the group response. Next, finite element analyses of corresponding unit cells and single columns are performed. Reasonable correlations of load responses are found between single column and group behavior. Group and single column responses are then used to investigate Sg/S1 relationship with different foundation parameters, where Sg and S1 represent the settlement of the group and single column, respectively.

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Shaat, Amr, and Amir Fam. "Axial loading tests on short and long hollow structural steel columns retrofitted using carbon fibre reinforced polymers." Canadian Journal of Civil Engineering 33, no. 4 (April 1, 2006): 458–70. http://dx.doi.org/10.1139/l05-042.

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This paper describes the behaviour of axially loaded short and long square hollow structural section (HSS) columns, strengthened with carbon fibre reinforced polymer (CFRP) sheets. Twenty-seven short-column and five long-column HSS specimens were tested. The effect of CFRP sheet orientation in the longitudinal and transverse directions was studied for short columns. For long columns, CFRP sheets were oriented in the longitudinal direction only. A maximum strength gain of 18% was achieved for short columns with two transverse CFRP layers. For long columns, the maximum strength gain of 23% was achieved with three longitudinal CFRP layers applied on four sides. In all CFRP-strengthened long columns, lateral deflections were reduced. Strength gain in long columns was highly dependent on the column's imperfection. As such, no correlation was established between strength gain and number of CFRP layers. CAN/CSA 16-01 equation was modified to account for CFRP through transformed section analysis so that they could be used to predict the axial-load capacity of long columns.Key words: retrofit, steel, HSS, column, FRP, carbon, buckling, strength, stiffness.

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Tao, Song Lei, Xing Ge Lian, Zi He Zhang, Yuan Hong Yu, and Zhi Fang Zhao. "A New Technique of Low-Pressure Long-Distance Soft Clay Pipeline Transportation." Advanced Materials Research 446-449 (January 2012): 2763–69. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.2763.

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A new technique of long-distance pipeline transportation of soft clay, which is related to Non Newton--Bingham pipe flow studies. Propose a method of non-continuous pneumatic conveying method with surface film lubrication, which will obviously reduce the friction between pipe wall and mud column and the Viscous resistance of clay. The air is injected to form air-column between mud columns. Adjust the lengths of mud column and air column and their proportion, and make the pushing force bigger than or near equivalent to the resistant force, until the optimum air-mud ratio for the required delivery distance is achieved. Long distance transportation of soft clay through low pressure pipeline is achieved. The method, with the features of energy-saving, high efficiency, profitable, can be applied in fields of water conservancy, petroleum, chemical, mining, and environmental protection, etc.

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Lu, Guan Hong, and Zhan Wang. "Test Scheme and Result Analysis of New-Type Frame Structure with Column End of Steel-Concrete Composite Joint." Advanced Materials Research 919-921 (April 2014): 247–53. http://dx.doi.org/10.4028/www.scientific.net/amr.919-921.247.

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The frame column and frame structure with column end of steel-concrete composite joint is a new-type architectural structure. To obtain the mechanical property of the new-type frame column and frame structure, comparative tests between 6 new-type columns and 3 ordinary columns and comparative tests between new-type frames and ordinary frames are carried out. This paper elabrately introduces the specimen design, experiment load, test program, test results and others. Thus, the transformation and failure characteristics of new-type long and short columns at different axial compression ratios and the transformation and failure characteristics of new-type grames at different prestresses are obtained. They are respectively compared with the ordinary long and short columns and frames. Results show that the seismic performance of the new-type column and frame structure is obviously superior to that of the ordinary ones. The tests can achieve the expected test objectives and are proved successful.

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5

Zhang, Zhen Peng, Jin Qiu Shao, Xue Yan Sun, and Hui Jun Liu. "Simulation of Soil Water and Salt Transport with Sand Column in Coastal Saline Soil Based on COMSOL." Applied Mechanics and Materials 614 (September 2014): 668–71. http://dx.doi.org/10.4028/www.scientific.net/amm.614.668.

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In the paper, transport of water and Cl- under leaching was 2D-digitally simulated with COMSOL Multi-physics. In a two-dimensional transient cross-sectional model. COSMOL was used to investigate water and solute transport in the soil column coupled with variable sand column forms, with “a” denoting no sand column, “b” with one vertical middle sand column, “c “ with one long Slanted sand column, “d” with two long Slanted X-shaped sand columns. The parameters of the model were primarily based on the soil physical properties measured at coastal clay loam saline soil in Tianjin. The simulation results showed that, given same initial and same boundary conditions, sand column increased the transport efficiency of water and salt, which depends on the position and angle of sand column accordingly. The slanted columns were overall superior to the vertical ones in transport efficiency. In sum, “d” was the best type, “c” was the second best and “b” was the third, according to the efficiency of salt leaching and the efficiency of the utilization of water resources.

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Jones, N. B., K. Riedel, W. Allan, S. Wood, P. I. Palmer, K. Chance, and J. Notholt. "Long-term tropospheric formaldehyde concentrations deduced from ground-based fourier transform solar infrared measurements." Atmospheric Chemistry and Physics 9, no. 18 (September 24, 2009): 7131–42. http://dx.doi.org/10.5194/acp-9-7131-2009.

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Abstract. We report a 13-year (1992–2005) dataset of total column measurements of formaldehyde (HCHO) over Lauder, New Zealand, inferred from solar infrared spectra measured using a high-resolution Fourier Transform Spectrometer (FTS). Ambient HCHO concentrations at this rural location are often close to levels typical of remote marine environments (<250 ppt), which are close to the detection limit using standard techniques. Consequently we develop a new method that successfully produces HCHO columns with sufficient sensitivity throughout the whole season. HCHO columns over Lauder have a strong seasonal cycle (±50%), with a mean column of 4.9×1015 molecules cm−2, peaking during summer months. A simple box model of CH4 oxidation reproduces the observed broad-scale seasonal cycle, but significantly underestimates the seasonal peak HCHO ground concentrations during summer. This suggests the existence of an additional significant source of HCHO, possibly isoprene that cannot be explained by oxidation of CH4 alone. The ground-based FTS column data compare well with collocated HCHO column measurements from the Global Ozone Monitoring Experiment (GOME) satellite instrument during the operational period of GOME (1996–2001, r2=0.65, mean bias=10%, n=48).

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7

Ragheb, M. S. "Ultrasonic frequency driven long plasma column." Review of Scientific Instruments 73, no. 11 (November 2002): 3818–24. http://dx.doi.org/10.1063/1.1512333.

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Kalbach, James. "IA column: Navigating the long tail." Bulletin of the American Society for Information Science and Technology 34, no. 2 (September 17, 2008): 36–38. http://dx.doi.org/10.1002/bult.2008.1720340211.

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9

Shoeib Soliman, Ata El-kareim. "Behavior of long confined concrete column." Ain Shams Engineering Journal 2, no. 3-4 (September 2011): 141–48. http://dx.doi.org/10.1016/j.asej.2011.09.003.

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Stapleton, Seth E., Cole C. McDaniel, William F. Cofer, and David I. McLean. "Performance of Lightly Confined Reinforced Concrete Columns in Long-Duration Subduction Zone Earthquakes." Transportation Research Record: Journal of the Transportation Research Board 1928, no. 1 (January 2005): 184–92. http://dx.doi.org/10.1177/0361198105192800120.

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The main goals of this research were to evaluate typical 1950s and 1960s as-built bridge columns in western Washington State in large subduction zone earthquakes and to investigate the dependency of failure mechanisms on loading history. Eight displacement histories were applied to eight nominally identical, half-scale, circular reinforced concrete columns expected to respond primarily in flexure (flexure-dominated). The main design deficiencies were a short longitudinal reinforcement lap splice at the base of the column (35 db) and inadequate transverse reinforcement. Test results showed that the failure mode of reinforced concrete columns was controlled by the column loading history. Three distinct failure mechanisms were observed for columns with an aspect ratio of approximately 4.2, assuming symmetric, double-curvature behavior. Large initial displacements greater than six times the effective yield displacement (Δ y) were likely to result in shear failures. Columns experiencing many displacements less than 4Δ y were likely to fail because of longitudinal reinforcement buckling. Columns subjected to several displacement excursions less than 4Δ y followed by an excursion greater than 6Δ y were likely to fail by longitudinal reinforcement slipping within the splice region. Despite the deficiencies present in circular reinforced concrete bridge columns built before 1975 in western Washington State, this study showed that flexure-dominated columns with a 35 db lap splice in multiple-column bent, three-or four-span bridges were not likely to experience significant damage in the predicted Cascadia Subduction Zone earthquake. However, other components of the bridge need to be assessed to determine whether the global bridge response is acceptable under the predicted Cascadia Subduction Zone earthquake.

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Jones, N. B., K. Riedel, W. Allan, S. Wood, P. I. Palmer, K. Chance, and J. Notholt. "Long-term tropospheric formaldehyde concentrations deduced from ground-based fourier transform solar infrared measurements." Atmospheric Chemistry and Physics Discussions 7, no. 5 (October 12, 2007): 14543–68. http://dx.doi.org/10.5194/acpd-7-14543-2007.

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Abstract. Long-term total column measurements of formaldehyde (HCHO) covering a 12 year period from 1992 to 2004 are reported from spectra recorded with a high-resolution Fourier Transform Spectrometer (FTS) using the sun as a light source at a Southern Hemisphere site (Lauder, New Zealand). The ambient HCHO concentrations at this rural location are often at background levels (<250 ppt) typical for remote marine environments. Due to these low values of HCHO, which are often at or below the detection limit of standard techniques, a method of analysis has been developed that successfully produces HCHO columns with sufficient sensitivity throughout the whole season. The HCHO column over Lauder was found to have a strong seasonal cycle (±50%), with a mean column of 4.2×1015 molecules cm−2, the maximum occurring in the summer. A simple box model of CH4 oxidation reproduces the seasonal cycle, but significantly underestimates the maximum HCHO ground concentrations deduced from the column observations, particularly in summer. This implies the existence of a significant source of HCHO that cannot be explained by oxidation of CH4 alone. The ground-based FTS column data compares well with collocated HCHO column measurements from the Global Ozone Monitoring Experiment (GOME) satellite instrument (r2=0.65, mean bias=10%, n=48).

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12

Wu, Shixu, Keting Tong, Jianmin Wang, and Yushun Li. "Experimental and Analytical Study on Creep Characteristics of Box Section Bamboo-Steel Composite Columns under Long-Term Loading." Materials 14, no. 4 (February 19, 2021): 983. http://dx.doi.org/10.3390/ma14040983.

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To expand the application of bamboo as a building material, a new type of box section composite column that combined bamboo and steel was considered in this paper. The creep characteristics of eight bamboo-steel composite columns with different parameters were tested to evaluate the effects of load level, section size and interface type under long-term loading. Then, the deformation development of the composite column under long-term loading was observed and analyzed. In addition, the creep-time relationship curve and the creep coefficient were created. Furthermore, the creep model of the composite column was proposed based on the relationship between the creep of the composite column and the creep of bamboo, and the calculated value of creep was compared with the experimental value. The experimental results showed that the creep development of the composite column was fast at first, and then became stable after about 90 days. The creep characteristics were mainly affected by long-term load level and section size. The creep coefficient was between 0.160 and 0.190. Moreover, the creep model proposed in this paper was applicable to predict the creep development of bamboo-steel composite columns. The calculation results were in good agreement with the experimental results.

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13

Humanists, Climate. "Editor's Column." PMLA/Publications of the Modern Language Association of America 133, no. 1 (January 2018): 9–18. http://dx.doi.org/10.1632/pmla.2018.133.1.9.

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Just how important is “big data” to humanists? is it mostly hype and hot air, as argued by Timothy Brennan in “The Digital Humanities Bust”? Or is it a genuine new beginning, as argued by Sarah E. Bond, Hoyt Long, and Ted Underwood in response? And what exactly does “big” mean? Is the magnitude necessarily the result of algorithmic computation, a form of digital humanities based on data mining and yielding statistical observations about large corpora? Or could it be nonalgorithmic, coming from collaboration, say, rather than computation? Bond, Long, and Underwood point out that big data projects might look different in the future, transformed by new partnerships with libraries and museums. What might some of these projects be?

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14

Lukáš, D., and J. Chaloupek. "Wetting between parallel fibres; column-unduloid and column disintegration transitions." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 217, no. 4 (April 1, 2003): 273–77. http://dx.doi.org/10.1243/095441103322060721.

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Wetting phenomena are studied for a fibre bundle consisting of three parallel cylinders of radius b. Two types of long liquid column (a disintegrated and a channel-filling column) and a state akin to the unduloid can form, depending on whether the cylinder-cylinder separation, 2 d, is larger or smaller than certain critical values. The dimensionless threshold values d/b have been calculated, when gravity can be neglected and the liquid-fibre contact angle is zero. The threshold value for the morphological transition between disintegrated columns and channel-filling columns occurs for ( d/b)tr1 = 0.07869, and the transition between channel-filling column and unduloid sets in when ( d/b)tr2 = 2.85337. The existence of the first type of morphological transition is validated by computer simulation based on the Ising model and the Monte Carlo method, as well as by experiments carried out with steel cylinders and epoxy resin.

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15

FERREIRA, D. B., R. B. GOMES, A. L. CARVALHO, and G. N. GUIMARÃES. "Behavior of reinforced concrete columns strenghtened by partial jacketing." Revista IBRACON de Estruturas e Materiais 9, no. 1 (February 2016): 1–21. http://dx.doi.org/10.1590/s1983-41952016000100002.

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This article presents the study of reinforced concrete columns strengthened using a partial jacket consisting of a 35mm self-compacting concrete layer added to its most compressed face and tested in combined compression and uniaxial bending until rupture. Wedge bolt connectors were used to increase bond at the interface between the two concrete layers of different ages. Seven 2000 mm long columns were tested. Two columns were cast monolithically and named PO (original column) e PR (reference column). The other five columns were strengthened using a new 35 mm thick self-compacting concrete layer attached to the column face subjected to highest compressive stresses. Column PO had a 120mm by 250 mm rectangular cross section and other columns had a 155 mm by 250mm cross section after the strengthening procedure. Results show that the ultimate resistance of the strengthened columns was more than three times the ultimate resistance of the original column PO, indicating the effectiveness of the strengthening procedure. Detachment of the new concrete layer with concrete crushing and steel yielding occurred in the strengthened columns.

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Sivakumar, V., D. McKelvey, J. Graham, and D. Hughes. "Triaxial tests on model sand columns in clay." Canadian Geotechnical Journal 41, no. 2 (April 1, 2004): 299–312. http://dx.doi.org/10.1139/t03-097.

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Vibro-stone columns can improve the bearing capacity and reduce the settlement of foundations. Their performance depends on the strength of the column material, reinforcement method of column installation, type of in situ soil, area replacement ratio, and column length. This paper examines the behaviour of small laboratory specimens of soft clay (undrained shear strength ≈ 30 kPa) reinforced with sand columns when tested under known boundary stress conditions. Two series of tests were carried out on kaolin specimens (diameter 100 mm, height 200 mm) in a triaxial cell. In the first series, specimens were reinforced with a 32 mm diameter column of sand, 80, 120, 160, or 200 mm long. Columns were installed by (i) compacting moist sand into a prebored hole or (ii) freezing a column of moist sand before inserting it into a prebored hole. In the second series, columns were reinforced with geo-grids before installation. The specimens were subjected to (i) uniform loading in which the load was applied over the entire surface area of the specimen or (ii) foundation-type loading in which only a small area in the centre of the specimen was loaded. Under uniform loading, the specimens containing a full-depth column were significantly stronger than specimens without columns. Specimens with single, partially penetrating columns installed by wet compaction were weaker than specimens without columns. When frozen columns were installed, strengths increased progressively. Under foundation-type loading, bearing capacities increased with an increase in column length. Geo-grid reinforcement produced significant increases in load-carrying capacity.Key words: ground improvement, undrained shear strength, consolidation, stress path.

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SHIBATA, Michio. "LONG COLUMN EFFECT OF A COMPOSITE BEAM-COLUMN SUBJECTED TO NON-SYMMETRIC BENDING." Journal of Structural and Construction Engineering (Transactions of AIJ) 68, no. 568 (2003): 147–52. http://dx.doi.org/10.3130/aijs.68.147_1.

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Harrison, Penny. "Weathering a long pandemic." Gastrointestinal Nursing 19, no. 1 (February 2, 2021): 50. http://dx.doi.org/10.12968/gasn.2021.19.1.50.

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Kadhim, Shaymaa Tareq, and Ziad Bashar Fouad. "Stability analysis of roadway embankments supported by stone columns with the presence of water table under short-term and long-term conditions." MATEC Web of Conferences 162 (2018): 01013. http://dx.doi.org/10.1051/matecconf/201816201013.

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Use of stone column technique to improve soft foundation soils under roadway embankments has proven to increase the bearing capacity and reduce the potential settlement. The potential contribution of stone columns to the stability of roadway embankments against general (i.e. deep-seated) failure needs to be thoroughly investigated. Therefore, a two-dimensional finite difference model implemented by FLAC/SLOPE 7.0 software, was employed in this study to assess the stability of a roadway embankment fill built on a soft soil deposit improved by stone column technique. The stability factor of safety was obtained numerically under both short-term and long-term conditions with the presence of water table. Two methods were adopted to convert the three-dimensional model into plane strain condition: column wall and equivalent improved ground methods. The effect of various parameters was studied to evaluate their influence on the factor of safety against embankment instability. For instance, the column diameter, columns’ spacing, soft soil properties for short-term and long-term conditions, and the height and friction angle of the embankment fill. The results of this study are developed in several design charts.

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Abdel-Aal, El-Sayed M., Kaddus Miah, J. Christopher Young, and Iwona Rabalski. "Comparison of Four C18 Columns for the Liquid Chromatographic Determination of Deoxynivalenol in Naturally Contaminated Wheat." Journal of AOAC INTERNATIONAL 90, no. 4 (July 1, 2007): 995–99. http://dx.doi.org/10.1093/jaoac/90.4.995.

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Abstract Three long and 1 short reversed-phase C18 columns were compared for separation of deoxynivalenol (DON) in extracts of naturally contaminated wheat samples using liquid chromatography with ultraviolet detection and liquid chromatography/mass spectrometry (LC/MS). Among the 3 long columns used, a Symmetry C18 column with an isocratic solvent mixture of wateracetonitrilemethanol (90 + 5 + 5, v/v/v) gave the best separation for DON without interferences from other compounds in the wheat extracts. The Symmetry short (75 mm) column was comparable with the long column (250 mm) in resolving DON but significantly reduced retention time (i.e., 5.8 versus 16.3 min). Increasing the column temperature from 25 to 45C resulted in a further reduction in retention time. Identity of DON in the wheat extracts and standard solutions was confirmed by LC/MS in the positive ion mode, whereby DON appeared with an (M+1)+ ion at a mass-to-charge ratio of 297 plus fragment ions associated with loss of water and/or a 30 atomic mass unit (amu) CH2O fragment. The Symmetry short column was also capable of separating a mixture of the mycotoxins DON, 15-acetyl-DON, nivalenol, and zearalenone by use of a combination of an isocratic and gradient solvent system. The overall method showed high precision, exhibiting a relative standard deviation of 4.8%, limit of detection of 50 ng/g, and limit of quantitation of 165 ng/g. It was significantly correlated with enzyme-linked immunosorbent assay analysis, indicating its appropriateness for safety and quality assurance of wheat and related grains.

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Sun, Yue Dong, and Yu Ming Lin. "The Effect on The Overall Performance of Frame Structure of Local Column Destruction." Applied Mechanics and Materials 71-78 (July 2011): 315–20. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.315.

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How to ensure the whole stability of structure and avoid progressive collapse of structure caused by destruction of local structures under accidental loading have been paid close attention to extensively by researchers all over the world. According to GSA guidelines, FEM model of 3-D frame structure was established by ANSYS software. Failure of frame structure local column is simulated with the method of "killing" columns of long side, short side, corner side, and interior side, and two columns of long sides, in order to explore the regularity for change of series performance parameters when the frame structure suffering accidental loading. And the alternative load path method was used to analyse the collapse of reinforced concrete frame structure. The result indicates that the frame structure local column damage can make structure basic natural vibration period and maximum interlayer displacement angle larger, and make minimum ratio between shearing force and weight smaller, and if two columns of long side are destroyed, the progressive collapse of frame structure will occur.

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Hatfield, Robert G., and Andrew D. Turner. "Rapid Liquid Chromatography for Paralytic Shellfish Toxin Analysis Using Superficially Porous Chromatography with AOAC Official MethodSM 2005.06." Journal of AOAC INTERNATIONAL 95, no. 4 (July 1, 2012): 1089–96. http://dx.doi.org/10.5740/jaoacint.12-005.

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Abstract The bioaccumulation of paralytic shellfish toxins in mussels, oysters, cockles, hard clams, razors, and king scallops is monitored in England, Scotland, and Wales by AOAC Official MethodSM 2005.06 LC-with fluorescence detection (FLD). One of the commonly perceived disadvantages of using this method is the long turnaround time and low throughput in a busy laboratory environment. The chromatographic analysis of each sample typically utilizes a 15 min cycle time to achieve toxin oxidation product separation and column equilibration prior to subsequent analysis. A standard RP C18 analytical column, used successfully in recent years, achieves good separation with a long column lifetime. The analysis of a 40 sample qualitative screening batch takes approximately 18 h, including blanks, standards, and other QC samples. The availability of superficially porous column technology has offered the potential to reduce analysis time while retaining column performance on existing hardware. In this study, AOAC Official Method 2005.06 with LC-FLD was transferred to two different commercially available superficially porous columns, and the method performance characteristics were evaluated. Both columns separated all toxins adequately with cycle times less than half that of the existing method. Linearity for each toxin was acceptable up to two times the European maximum permitted limit of 800 μg di-HCl saxitoxin equivalent/kg flesh. LOD and LOQ values were substantially improved for the majority of toxins, with gonyautoxin 1&4 and neosaxitoxin showing up to a two- and four-fold improvement, respectively, depending on the column used. Quantification results obtained from parallel analysis of contaminated samples were acceptable on both columns. Comparative screen results gave a slight increase in the occurrence of contaminated samples, which was attributed to the improved detection limit for most toxins. Issues with rapidly increasing back pressure, however, were identified with both columns, with a limit of around 500 injections. This compares to the >3000 cycles routinely obtained with the standard RP-C18 HPLC columns currently in use. Overall, the gain achieved with these columns through shorter analysis time and improved analytical sensitivity is potentially of benefit in a high-throughput environment. For the routine high-throughput screening of shellfish samples, however, an improved column lifetime is desirable.

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Papiol, Gemma Giménez. "A Natural and Concurrent Interferent in Bolinus brandaris with Consequences on Amnesic Shellfish Poisoning Risk Management." Journal of AOAC INTERNATIONAL 98, no. 1 (January 1, 2015): 82–84. http://dx.doi.org/10.5740/jaoacint.14-140.

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Abstract Regulations aimed to protect public health from amnesic shellfish poisoning (ASP) are focused on the detection and accurate quantification of domoic acid(DA). The reference detection determination used by the different shellfish safety monitoring agencies worldwide is HPLC separation followed by UV detection, in which different chromatographic column lengths or brands are accepted as long as it is C18 column. A laboratory validation of this method showed different performance of two accepted chromatographic columns when analyzing Bolinus brandaris samples. A natural compound, present only in those samples that contained DA, was evidencedby one of the columns. The DA quantification obtained with the column that coelutes both compounds was approximately twice the amount obtained with the column that separates them. This difference has important consequences in the ASP toxins management for thisfishery. The identity and toxicity of the compound are still unknown.

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Li, Guo Chang, Bo Wen Zhu, and Yu Liu. "Finite Element Simulation on Behavior of the High-Strength Concrete Filled High-Strength Square Steel Tube Middle-Long Columns under Axial Compressive Load." Applied Mechanics and Materials 578-579 (July 2014): 340–45. http://dx.doi.org/10.4028/www.scientific.net/amm.578-579.340.

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In this paper, using ABAQUS, 16 high-strength concrete filled high-strength square steel tube middle-long columns’ axial compression process were simulated. The load-deflection relationships were obtained and the new combination in improving the bearing capacity and plastic deformation has a great advantage. Realization of length variation slenderness ratio by changing the length of column, this paper also study the influence of slenderness ratio, the main parameters of the high-strength concrete filled high-strength square steel tube middle-long column. It is found that both bearing capacity and the plastic capacity are associated with slenderness ratio.

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Aryan, Hadi. "Seismic Resistant Bridge Columns with NiTi Shape Memory Alloy and Ultra-High-Performance Concrete." Infrastructures 5, no. 12 (November 30, 2020): 105. http://dx.doi.org/10.3390/infrastructures5120105.

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Reinforced concrete bridge columns often endure significant damages during earthquakes due to the inherent deficiencies of conventional materials. Superior properties of the new materials such as shape memory alloy (SMA) and ultra-high-performance concrete (UHPC), compared to the reinforcing steel and the normal concrete, respectively, are needed to build a new generation of seismic resistant columns. Application of SMA or UHPC in columns has been separately studied, but this paper aims to combine the superelastic behavior of NiTi SMA and the high strength of UHPC, in order to produce a column design with minimum permanent deformation and high load tolerance subjected to strong ground motions. Additionally, the excellent corrosion resistance of NiTi SMA and the dense and impermeable microstructure of UHPC ensure the long-term durability of the proposed earthquake resistant column design. The seismic performance of four columns, defined as steel reinforced concrete (S-C), SMA reinforced concrete (SMA-C), SMA reinforced UHPC (SMA-UHPC), and reduced SMA reinforced UHPC (R-SMA-UHPC) is analyzed through a loading protocol with up to 4% drift cycles. The use of NiTi SMA bars for the SMA reinforced columns is limited to the plastic hinge region where permanent deformations happen. All the columns have 2.0% reinforcement ratio, except the R-SMA-UHPC column that has a 1.33% reinforcement ratio to optimize the use of SMA bars. Unlike the S-C column that showed up to 68% residual deformation compared to peak displacement during the last loading cycle the SMA reinforced columns did not experience permanent deformation. The SMA-C and R-SMA-UHPC columns showed similar strengths to the S-C column, but with about 5.0- and 6.5-times larger ductility, respectively. The SMA-UHPC column showed 30% higher strength and 7.5 times larger ductility compared to the S-C column.

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OBRYK, M. K., P. T. DORAN, J. A. HICKS, C. P. McKAY, and J. C. PRISCU. "Modeling the thickness of perennial ice covers on stratified lakes of the Taylor Valley, Antarctica." Journal of Glaciology 62, no. 235 (June 7, 2016): 825–34. http://dx.doi.org/10.1017/jog.2016.69.

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ABSTRACTA 1-D ice cover model was developed to predict and constrain drivers of long-term ice thickness trends in chemically stratified lakes of Taylor Valley, Antarctica. The model is driven by surface radiative heat fluxes and heat fluxes from the underlying water column. The model successfully reproduced 16 a (between 1996 and 2012) of ice thickness changes for the west lobe of Lake Bonney (average ice thickness = 3.53 m) and Lake Fryxell (average ice thickness = 4.22 m). Long-term ice thickness trends require coupling with the thermal structure of the water column. The heat stored within the temperature maximum of lakes exceeding a liquid water column depth of 20 m can either impede or facilitate ice thickness change depending on the predominant climatic trend (cooling or warming). As such, shallow (<20 m deep water columns) perennially ice-covered lakes without deep temperature maxima are more sensitive indicators of climate change. The long-term ice thickness trends are a result of surface energy flux and heat flux from the deep temperature maximum in the water column, the latter of which results from absorbed solar radiation.

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Shvydky, A., V. N. Khudik, C. E. Theodosiou, and V. P. Nagorny. "Dynamic positive column in long-gap barrier discharges." Journal of Applied Physics 99, no. 1 (January 2006): 013303. http://dx.doi.org/10.1063/1.2158139.

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Ghaddar, Maha G. "Effect of Hollow Shape on the Behavior of Reinforced Self-Compacting Concrete Slender Column Under Eccentric Loading." Engineering and Technology Journal 39, no. 6 (June 25, 2021): 884–92. http://dx.doi.org/10.30684/etj.v39i6.1504.

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Results of testing reinforced self-compacted concrete slender columns having longitudinal holes concealing PVC pipe in their cross sections under axial compression load and uniaxial bending are presented in this paper. The effect of hollow shape on the performance of slender columns having 200x200mm quadratic cross section and 1300mm long under concentric and eccentric loads was investigated. Three different shapes of central hole: circular, square, and lozenge pattern in addition to the different load eccentricity values were considered to investigate the axial loading resistance and cracking load, lateral and longitudinal deflections of the columns. Test results have showed that altering the hollow shape inside the area of column cross section does not show a great influence on the column behavior unless the hollow ratio changed. The effect of hole shape or the hollow ratio on loading capacity is insignificant but the existence of a hole embedded longitudinally in the column significantly decreases its ultimate capacity. The effect of hollow shape or hollow ratio on a slender columns behavior subjected to eccentric loading with small ratio of load eccentricity to total column thickness (e/h=.33) was more than that of large eccentricity (e/h=1.0). Accordingly, the decrease in loading column capacity of columns was (5.0%, 2.5%, and 6.6%) compared to (3.2%, 2.2%, and 4.7%) for the same hole shapes respectively.

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29

Cao, Bao Zhu, Yao Chun Zhang, and Yue Ming Zhao. "Experimental Research on Concrete Filled Thin-Walled Steel Tube Long Columns." Key Engineering Materials 400-402 (October 2008): 551–57. http://dx.doi.org/10.4028/www.scientific.net/kem.400-402.551.

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Experimental research on square and octagonal concrete filled thin-walled steel tube long columns of 6 specimens in axial compression and 8 specimens in eccentric compression is undertaken. The relationship of global buckling bearing capacity of the columns and local buckling of the steel tubes is obtained. The test indicates that local buckling occurs in steel tube of each column before it reaches ultimate capacity, and has little effect on global buckling performance. The ultimate load decreases obviously with the increase of slender ratio and eccentricity. The ductility of columns increases with the increase of steel ratio in composite sections. Composite beam element of ANSYS is adopted in the finite element analysis. The theoretical results are agreed well with test..

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30

Mohd Sani, Mohd Syahrul Hisyam, Fadhluhartini Muftah, and Cher Siang Tan. "Investigation on Mechanical Performance of Slender Cold-Formed Steel Channel Column." Key Engineering Materials 706 (August 2016): 107–11. http://dx.doi.org/10.4028/www.scientific.net/kem.706.107.

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Cold-formed steel (CFS) is steel based material that has been used broadly in construction and building as non-structural or structural element. Many researchers are studying the CFS as structural element, such as column, beam and roof truss. With a lot of advantages, CFS becoming more popular when distinguished by other material. CFS also owned the unstable and unsafe circumstances when the section in a slender or long column. The main issue that influenced the unstable circumstances for slender column is recognised as local, distortional and global buckling. As a result, the study of the mechanical performance of slender column must be investigated to get some important information for design and analysis intention. Three samples of CFS channel column with a height of 1000, 1500 and 2000 mm are determined. From the testing, the ultimate load of the slender CFS column decreases with increasing of the height of the column. All columns are illustrated having the global buckling when subjected to load. The flange and web deformation of the column is becoming not stiff when the height of the column is increased.

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31

Baláž, Ivan, Yvonna Koleková, and Lýdia Moroczová. "Built-up CFS column with lacings and battens." MATEC Web of Conferences 310 (2020): 00025. http://dx.doi.org/10.1051/matecconf/202031000025.

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The built-up columns are generally used in industrial buildings, either as posts for cladding when their buckling length is very long, or as columns supporting a crane girder. The built-up columns are composed usually of two parallel chords interconnected by lacings or battens. In the paper the special type of built-up column will be analysed from Llentab Company. It consists from four parallel chords with cold-formed C cross-sections which are interconnected by lacing in one plane and by battens in four perpendicular planes. Such types of columns are especially convenient for the relatively high light steel halls. Analysis of the behaviour of such column will be performed: a) on the model with smeared equivalent bending and shear stiffness’s using analytical solution, b) on the discrete model using FEM and commercial program ANSYS. The theory of the second order taking into account the initial imperfections and the shear deformations will be employed.

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32

Aquino, Denis D., Janice P. Mallillin, Ramoncito F. Sulit, Frederick C. Hila, Ivy Angelica A. Nuñez, and Adelina D. M. Bulos. "Performance evaluation of a rectifier column using gamma column scanning." Nukleonika 62, no. 4 (December 1, 2017): 285–87. http://dx.doi.org/10.1515/nuka-2017-0041.

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Abstract Rectifier columns are considered to be a critical component in petroleum refineries and petrochemical processing installations as they are able to affect the overall performance of these facilities. It is deemed necessary to monitor the operational conditions of such vessels to optimize processes and prevent anomalies which could pose undesired consequences on product quality that might lead to huge financial losses. A rectifier column was subjected to gamma scanning using a 10-mCi Co-60 source and a 2-inch-long detector in tandem. Several scans were performed to gather information on the operating conditions of the column under different sets of operating parameters. The scan profiles revealed unexpected decreases in the radiation intensity at vapour levels between trays 2 and 3, and between trays 4 and 5. Flooding also occurred during several scans which could be attributed to parametric settings.

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33

Khenyab, Ali Y., Hussein F. Ajaj, and Rawa A. Helal. "THE ELASTIC BUCKLING BEHAVIOR OF (5056-H18)ALALLOY COLUMNS UNDER VARIABLE LOAD." IRAQI JOURNAL FOR MECHANICAL AND MATERIALS ENGINEERING 19, no. 2 (May 26, 2019): 183–92. http://dx.doi.org/10.32852/iqjfmme.v19i2.317.

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The research deals the evaluation of buckling behavior for 5056-H18 Al alloy columnsunder variable loads and studies the effect of initial deflection on the critical buckling load.Seven samples were used for the purpose of testing the buckling of the column. The criticaldeflection of the column can be determined by measuring a length multiplied by 0.01 andthis is the critical load of the columns. For the purpose of measuring the critical deviation ofthe column, a digital dial gauge has been applied and it set at 0.7 distance from the length ofthe column from the fixed condition. The experimental results were compared with thePerry - Robertson formula, Euler's theory for long columns and with the values calculatedfrom the ANSYS 17 program. It has been observed that the Euler formula showed goodcompatibility with the practical results with safety factor 1.5. The ANSYS results showedwell agreement taking a 1.5 factor of safety. While the Perry-Robertson formula needs a 1.4safety factor to be safe results compared with experimental results.

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34

Chen, Jianfeng, Xinxin Yang, Shen Yongkang, and Mingqi Chen. "Experimental study on cold-formed steel lipped channel medium-long columns strengthened longitudinally by steel strips or steel bars." Advances in Structural Engineering 24, no. 12 (April 29, 2021): 2705–19. http://dx.doi.org/10.1177/13694332211011550.

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Based on the existing methods of reinforcing cold-formed steel lipped channel column, this paper proposed that reinforced the cold-formed steel lipped channel column longitudinally with steel strips or steel bars for the first time. In order to study the influence of section forms and initial stress ratio on axial compression behavior of columns, a series of pin-pin ends axial compression tests were conducted. The experiment specimens contained 20 concentrically loaded specimens with two cross-section shapes, four initial stress ratios, respectively. It was shown that when reinforcing column longitudinally with the reinforcement, under axial compression, the ultimate bearing capacity of the specimens could significantly increase with little change in the quantity of steel. Moreover, the reinforcing effect of the column decreased linearly with an increase in the initial stress ratio ( β) of the load-strengthened specimens. Here, unloading or partial unloading reinforcement was recommended, and the initial stress ratio should be lower than 0.3. Finally, the experimental results were compared with the calculation results for the axial bearing capacities of the column based on the current Chinese standard (GB50018-2002) and North American standard (AISI). It indicated that for the section prone to local-global interactive buckling, the result calculated by GB50018-2002 is more accurate, but has a large deviation in calculating the section prone to distortional buckling. Results of direct strength method of AISI are the opposite to the result of GB50018-2002.

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35

Kronik, John W. "Editor's Column." Publications of the Modern Language Association of America 101, no. 3 (May 1986): 307–8. http://dx.doi.org/10.1632/s0030812900135515.

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“A good read.” That expression is everywhere about us these days. However humble its beginnings, its incorporation into the critical lingo of the established literary press has vested it with apparent respectability. Before long, William Safire or another student of picturesque usage will comment on the origins and spurious legitimacy of this recent attachment to our linguistic arsenal. It is perhaps no accident that it was an expert on the allegory of language—and an erstwhile Californian—who introduced this designation some two years ago into the solemn deliberations of the PMLA editorial board. Unfortunately, I cannot recall the specific manuscript that incited this spontaneous and pithy assessment; but I do know that the newfound objective measure took immediate root as one of the board's many evaluative criteria. Most likely, the term fastened onto a way of perceiving and reading that we had been engaging in all along but for which no such neat tag had been readily available.

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36

Yuan, Yu Qing, Wei Li, Xue Chan Li, and Tao Guo. "Vibro-Replacement Stone Column Treating Silty Sand Soil Subgrade." Applied Mechanics and Materials 256-259 (December 2012): 1060–63. http://dx.doi.org/10.4028/www.scientific.net/amm.256-259.1060.

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To improve the wet soft silty sand bearing capacity, vibro-replacement stone column was used. Compared with the practical construction, this paper introduces the vibro-replacement stone column strengthening soft foundation. The principle of the construction, quality control, and inspection technology were discussed. Based on Drucker - Prager elastic-plastic model, different high wet soft foundation was simulated with the numerical analysis software. Results show that vibro-replacement stone column can significantly reduce the roadbed horizontal displacement. The displacement of the subgrade reinforced by stone columns decreases respectively 0.1, 0.2, 0.6, 2.3 cm than the other. If the subgrade is 4 m in height, the displacement reaches 0.2, 0.5, 0.7 cm when the length of stone column is 5, 10, 15m, respectively. To sum up, five - metre long pile is more economic and reasonable.

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37

Lee, Seung Sik, Soo Ha Chae, Soon Jong Yoon, and Sun Kyu Cho. "A Study on the Design Curves for Pultruded Composite Columns." Advanced Materials Research 26-28 (October 2007): 337–40. http://dx.doi.org/10.4028/www.scientific.net/amr.26-28.337.

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The strengths of PFRP thin-walled columns are determined according to the modes of buckling which consist of local mode for short columns, global mode for long columns, and interaction mode between local and global modes for intermediate columns. Unlike the local and global buckling, the buckling strength of interaction mode is not theoretically predictable. Refined theoretical approaches which can account for different elastic properties of each plate component consisting of a PFRP thin-walled member are used. Based on both the analytical buckling loads and the experimentally measured buckling loads from literatures, the accuracies of Ylinen’s equation and modified AISC/LRFD column design equation for isotropic steel columns were compared. From the comparison, it was found that the modified AISC/LRFD column design equation is more suitable for the prediction of the buckling loads of PFRP thin-walled members than Ylinen’s equations.

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38

Tayeh, Bassam A., Mohammed Abu Naja, Samir Shihada, and Mohammed Arafa. "Repairing and Strengthening of Damaged RC Columns Using Thin Concrete Jacketing." Advances in Civil Engineering 2019 (June 11, 2019): 1–16. http://dx.doi.org/10.1155/2019/2987412.

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This research aims to investigate the efficiency of repairing damaged concrete columns using thin concrete jacketing. The experimental program included casting of nine reference 300 mm long reinforced concrete column specimens: three specimens had a cross-sectional dimension of 100 mm × 100 mm, three specimens had a cross-sectional dimension of 150 mm × 150 mm, and three specimens had a cross-sectional dimension of 170 mm × 170 mm. A total of 36 identical column cores were cast with similar cross sections of 100 mm × 100 mm and a height of 300 mm. These cores were damaged by loading them with approximately 90% of their actual ultimate axial load capacities. Then, the columns were repaired and strengthened by applying two jacketing materials, which were 25 and 35 mm thick, on all four sides. Group 1 consisted of 18 column cores jacketed by normal strength concrete with a maximum aggregate size of 4.75 mm and steel reinforcement, whereas Group 2 consisted of 18 column cores jacketed using ultrahigh-performance fibre-reinforced self-compacting concrete with steel reinforcement. The experimental program showed that the Group 1 specimens had ultimate load capacities more than twice those of the unjacketed reference columns and the same axial capacity as the monolithically cast reference columns. The Group 2 specimens showed a significant increase in ultimate load capacity, which was approximately 3 times that of the unjacketed reference column and 1.86 times that of the monolithically cast reference columns. Moreover, using the shear studs was found to be the most effective among the three surface preparation techniques.

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39

Sang, Xiahan, Adedapo A. Oni, and James M. LeBeau. "Atom Column Indexing: Atomic Resolution Image Analysis Through a Matrix Representation." Microscopy and Microanalysis 20, no. 6 (November 17, 2014): 1764–71. http://dx.doi.org/10.1017/s1431927614013506.

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AbstractHere, we report the development of an approach to map atomic resolution images into a convenient matrix representation. Through the combination of two-dimensional Gaussian fitting and the projective standard deviation, atom column locations are projected onto two noncollinear reference lattice vectors that are used to assign each a unique (i, j) matrix index. By doing so, straightforward atomic resolution image analysis becomes possible. Using practical examples, we demonstrate that the matrix representation greatly simplifies categorizing atom columns to different sublattices. This enables a myriad of direct analyses, such as mapping atom column properties and correlating long-range atom column pairs. MATLAB source code can be downloaded from https://github.com/subangstrom/aci.

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40

Palmer, Paul I., Michael P. Barkley, Thomas P. Kurosu, Alastair C. Lewis, Julie E. Saxton, Kelly Chance, and Luciana V. Gatti. "Interpreting satellite column observations of formaldehyde over tropical South America." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 365, no. 1856 (May 18, 2007): 1741–51. http://dx.doi.org/10.1098/rsta.2007.2042.

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Space-borne column measurements of formaldehyde (HCHO), a high-yield oxidation product of volatile organic compounds (VOCs), represent important constraints for quantifying net regional fluxes of VOCs. Here, we interpret observed distributions of HCHO columns from the Global Ozone Monitoring Experiment (GOME) over tropical South America during 1997–2001. We present the first comparison of year-long in situ isoprene concentrations and fire-free GOME HCHO columns over a tropical ecosystem. GOME HCHO columns and in situ isoprene concentrations are elevated in the wet and dry seasons, with the highest values in the dry season. Previous analysis of the in situ data highlighted the possible role of drought in determining the elevated concentrations during the dry season, inferring the potential of HCHO columns to provide regional-scale constraints for estimating the role of drought on isoprene emissions. The agreement between the observed annual cycles of GOME HCHO columns and Along-Track Scanning Radiometer firecount data over the Amazon basin (correlations typically greater than 0.75 for a particular year) illustrates the potential of HCHO column to provide quantitative information about biomass burning emissions.

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41

SHIBATA, Michio. "EFFECTIVE LENGTH OF A LONG COLUMN IN THE WELL." Journal of Structural and Construction Engineering (Transactions of AIJ) 68, no. 567 (2003): 133–39. http://dx.doi.org/10.3130/aijs.68.133.

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42

Khot, Subhash. "Guest column: inapproximability results via Long Code based PCPs." ACM SIGACT News 36, no. 2 (June 2005): 25–42. http://dx.doi.org/10.1145/1067309.1067318.

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43

Choo, C. C., H. Gesund, and I. E. Harik. "Influence of Long-Term Loads on Concrete Column Strength." Practice Periodical on Structural Design and Construction 8, no. 1 (February 2003): 57–60. http://dx.doi.org/10.1061/(asce)1084-0680(2003)8:1(57).

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44

Bauer, H. F. "Hydroelastic oscillations of a viscous infinitely long liquid column." Journal of Sound and Vibration 119, no. 2 (December 1987): 249–65. http://dx.doi.org/10.1016/0022-460x(87)90453-6.

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45

Najim, K., and V. Ruiz. "Long-range predictive control of an absorption packed column." Applied Mathematical Modelling 19, no. 1 (January 1995): 39–45. http://dx.doi.org/10.1016/0307-904x(94)00002-n.

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46

Li, Guangjun, Tianfang Mo, Ningbo Xu, Weixiong Zhang, Hanwen Lu, Deyuan Deng, and Mingbo Yi. "Subsection construction technology of rectangular concrete independent column with super high cross section." E3S Web of Conferences 293 (2021): 02004. http://dx.doi.org/10.1051/e3sconf/202129302004.

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With the progress of engineering technology, the ability of design and construction has been significantly improved, which the number of long-span construction and long-span Bridges and long-span steel structures are increasing more and more. As the main supporting members of Bridges and steel structures, the quality assurance of rectangular reinforced concrete independent columns is particularly important. In the implementation process of No.18 Maintenance Hangar Project of GAMECO Aircraft Maintenance Facility Phase III in Guangzhou Baiyun International Airport of China Southern Airlines, through research and practice, our company applied the subsection construction technology of super high section rectangular concrete independent columns, which can not only guarantee the quality and forming effect of the column body, but also reduce the input of formwork materials. Improve the utilization rate of formwork and scaffold effectively, and then reduce the input of turnover materials, and achieve remarkable results.

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47

Najim Abbas, Aamer, and Nura Jasim Muhammed. "Structural Behavior of Unbalanced Section self-compacting reinforced concrete axially Loaded columns." International Journal of Engineering & Technology 7, no. 4.37 (December 13, 2018): 127. http://dx.doi.org/10.14419/ijet.v7i4.37.24088.

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Eight (120 mm) square and (1 m) long reinforced concrete columns were tested under axial load to large inelastic deformations. The main purpose of this research was to investigate the behavior of column sections confined by rectilinear ties. Major variables considered in this program included: (1) Distribution of longitudinal and lateral steel, including unbalanced section due to the asymmetric distribution of reinforcing steel bars (2) type of concrete; normal concrete and self-compacting concrete. Finite element model was performed to validate the experimental results of this investigation. Test results indicate that a asymmetric distribution longitudinal bars results in desired performance of columns. Unsupported longitudinal bars and its number effective only at large deformations and result in rapid deterioration of column behavior at a later stage. There is 8.75% and 35.65% decrease in ultimate capacity under the control column, asymmetric distribution of reinforcing steel bars appears a more brittle while symmetric bars yields more elastic than brittle, it adds safety when failure happens.

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48

Jasim AL Akawai, Hussain, Khalid Mershid Aweed, and Shawthab Ali Jaber. "Finite Element Method Analysis of Normal and Corrosion Buckling with ANSYS17 Program for Stainless Steel 304 Alloy." International Journal of Engineering & Technology 7, no. 4.7 (September 27, 2018): 245. http://dx.doi.org/10.14419/ijet.v7i4.7.20557.

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In the present research the effect of corrosion on buckling behavior of 304 stainless steel with increasing of compressive dynamic loads was studied. There are two types of the columns, long columns and intermediate columns were used. For compression test, there are 24 columns specimens were used in the dynamic axis, 12 columns tests were carried out with increasing in the dynamic axis of compressive load, while for the corrosion test was performed by using 12 specimens were buried for two months under the ground before tested them. The allowable deflection in lateral axis is 1% in the length of column. When the deflection in lateral axis reaches 1% and does not increase more than it, and when removing the applied load, the column will return back to the normal state. This is defined critical buckling of columns. To calculate the original deflection. The digital gauge was employed at the distance about 0.7 for the column length at the fixed end of column. has alarm system was used to define critical buckling and to avoid the failure of the specimen and installed at the distance equal to 0.7 of the column length from fixed end. The empirical results showed that the effect of negatively corrosion on mechanical properties of alloys with 2.53% reduction of ultimate tensile strength comparing with non corroded specimens, in the other hand the corrosion will reduce the critical buckling load by 6% for two months. The experimental results comparing with the theoretical results obtained by Perry Robertson and Euler. Johnson with the results analyzed by ANASYS17. The results of this work are agreed with Perry-Robertson and Euler- Johnson by a safety factor about (1, 3) and 3 respectively while the results of ANASYS showed that agreement with the calculated and measured values by safety factor about (2).

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49

Ostrow, Steven F. "Paul V, the Column of the Virgin, and the New Pax Romana." Journal of the Society of Architectural Historians 69, no. 3 (September 1, 2010): 352–77. http://dx.doi.org/10.1525/jsah.2010.69.3.352.

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The sole surviving monumental column from the Basilica of Maxentius and Constantine is the focus of Paul V, the Column of the Virgin, and the New Pax Romana. In 1613 Pope Paul V removed and re-erected this column at the center of Piazza S. Maria Maggiore in Rome, crowning it with a gilded bronze statue of the Virgin and Child. After reconstructing the little-known history of the monument and situating it within the history of honorific columns and Paul's urban planning, Steven F. Ostrow examines the antiquarian interest it long held, what was known about its original context, and the symbolic associations with which it was endowed. This close reading of Paul's monument demonstrates how, by appropriating the column and topping it with a statue of the Virgin, the pope eloquently expressed the Church's longstanding belief in Mary as a bringer of peace and the protector of Rome.

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50

Alkhateeb, Fadi L., Taylor C. Hayward, and Kevin B. Thurbide. "A novel ultrashort capillary gas chromatography method using on-column injection and detection." Canadian Journal of Chemistry 94, no. 4 (April 2016): 259–64. http://dx.doi.org/10.1139/cjc-2015-0068.

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A novel method for ultrashort capillary column gas chromatography (GC) analysis is introduced, which employs on-column injection and detection and rapid temperature programming. Using 10–20 cm long capillary columns, results showed that the method provides efficient and very rapid separations for relatively simple mixtures. Moreover, the on-column aspect of the method used here is demonstrated to avoid the extra column analyte degradation that can occur in traditional approaches to such separations. As a result, the developed method allows for the first time the GC analysis of some very large and (or) highly thermally labile analytes, such as polypeptides and drug molecules that are normally prone to decomposition. As an application, this method is further used to monitor pharmaceutical degradant formation as a function of temperature and was found to provide similar results to those obtained from conventional high-performance liquid chromatography analysis. Overall, the findings indicate that this ultrashort GC column approach could be useful in these areas and potentially others, where relatively simple GC analysis and universal flame ionization detection is desirable.

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Journal articles on the topic 'Long Column'

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