Journal articles: 'Maximum Tension'

1

Denis Lavnikevich. "MAXIMUM TENSION." Current Digest of the Russian Press, The 72, no. 008 (February 23, 2020): 12. http://dx.doi.org/10.21557/dsp.58098897.

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Ahern, Tom. "Maximum tension palatoplasty." Journal of Equine Veterinary Science 25, no. 2 (February 2005): 46–47. http://dx.doi.org/10.1016/j.jevs.2005.01.004.

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Da̧browski, Mariusz P., and H. Gohar. "Abolishing the maximum tension principle." Physics Letters B 748 (September 2015): 428–31. http://dx.doi.org/10.1016/j.physletb.2015.07.047.

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Mortman, Nadav, Ramalakshmi Ramasamy, and Phillip Smith. "ELDERLY MOUSE DETRUSOR MAINTAINS ITS PEAK FORCE OF CONTRACTION OVER TIME." Innovation in Aging 6, Supplement_1 (November 1, 2022): 665. http://dx.doi.org/10.1093/geroni/igac059.2451.

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Abstract Aging is a risk factor for urinary dysfunction. Detrusor weakening has been thought to contribute to the old bladder phenotype. Animal detrusor strips have been used to study bladder function. Strength of contraction in detrusor strips depends on length. This is referred to as the “length-tension relationship.” The aim of our study was to investigate this relationship in a mouse model by comparing the length-tension relationship in old and mature mice. We hypothesize that aging is associated with no change in active detrusor tension capability, however maximal tension will occur at longer lengths.We used two groups of male C57/Bl6 mice for this study, mature 11-12 month old mice and old 22-23 month old mice. Longitudinal intact bladder strips were harvested and placed in a vertical tissue bath between tension recording transducer hooks. Passive tensions and KCl induced contraction tensions for step-wise increments of stretch were observed.In the old group, normalized strip length at the point of maximum active tension was increased by ~13% on average as compared to the mature group with a statistically significant difference (P value 0.0171). Interestingly, the maximum active tension between groups did not differ by age. In conclusion, detrusor from old mice achieve similar maximum active tensions as that from mature mice, however at an increased length. This finding argues against a common belief that the bladder weakens with age. Instead, the aging bladder may adapt to increased filling volumes with an ability to operate at a similar strength of a younger bladder.

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Deng, Peng, Rong Hua Huang, and Yin Jie Ma. "Improvement and Application of the Maximum Bubble Pressure Tensiometer." Applied Mechanics and Materials 333-335 (July 2013): 113–16. http://dx.doi.org/10.4028/www.scientific.net/amm.333-335.113.

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In order to measure the equilibrium surface tension of blended fuels, a tensiometer based on maximum bubble pressure method was built. Microscope was used to measure the capillary internal diameter precisely. And the operation guidelines of the tensiometer were calibrated by purified water to improve its accuracy. Then, the equilibrium surface tensions of bio-ethanol diesel fuels were investigated at a wide range of temperature and mass fractions. Results show that surface tension of blend fuels decrease linearly as temperature increases and decrease monotonically while ethanol mass fraction increases.

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Matsumoto, K. "Surface tension maximum of liquid 3He." Physica B: Condensed Matter 284-288 (July 2000): 198–99. http://dx.doi.org/10.1016/s0921-4526(99)02387-x.

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Novriandi, Dicky, Azriyenni Azhari Zakri, and Edy Ervianto. "Sag and Tension of 275 kV Transmission Line using Catenary." International Journal of Electrical, Energy and Power System Engineering 2, no. 3 (October 9, 2019): 15–20. http://dx.doi.org/10.31258/ijeepse.2.3.15-20.

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This research will develop a catenary method to determine the sag and tension analysis on the 275 kV transmission line conductors. The catenary method is dependent on the equation of the weight of the conductor, the maximum tensile stress of the conducting wire, the length of the span, and the maximum sag of the conductor. The method will be used in determining the value of sag and tension with the design of the model using software AutoCAD. The results of research for the same tower sag height of 6.86 m, with a tension of 4610.83 kg and a conductor length of 401.06 m, while sag for the tower is not the same height of 8.14 m, with a tension of 4612.84 kg, and changes in conductor length 401.06 m. The increase in current causes the sag value to increase, when the minimum current sag value is 6.9828 m, and the maximum current sag value increases to 8.44 m. While the tension will decrease along so that temperature is increased the current minimum pressure of 4531.27kg, and at the time of maximum tension of 3749.728kg. Sag and tension are also affected by ambient temperature when the minimum temperature is 20 ℃ sags are 6.8621 m and when the maximum temperature is 40 ℃ sag increases to 7.793492 m. Tension will decrease with each increase in temperature when the minimum temperature is 20 ℃ tension 4610.538 kg when the maximum temperature is 40 ℃ the tension is reduced to 4062.345 kg.

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CHEN, Pei Shan, and Mamoru KAWAGUCHI. "SHAPES OF MAXIMUM RIGIDITY FOR TENSION STRUCTURES." Journal of Structural and Construction Engineering (Transactions of AIJ) 60, no. 476 (1995): 113–20. http://dx.doi.org/10.3130/aijs.60.113.

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Cui, Peng, Yi Zhang, and Yuan Xue. "A novel method of analyzing spinning tensions for yarn breakage detection in ring frame." Journal of Engineered Fibers and Fabrics 15 (January 2020): 155892502090297. http://dx.doi.org/10.1177/1558925020902979.

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To reduce yarn breakage rates in spinning and increase production efficiency, we developed a detection device for spinning tension of the ring-spinning system by implementing the stress and displacement sensors with the yarn guide plate. The as-developed device receives data through signal acquisition system, and then the yarn tension at the thread guide and the displacement of the guide plate are obtained by solving the coupled physical-mathematical equations describing yarn tensions in twisting, ballooning, and winding processes, which gives the real-time dynamics. We found that the yarn tensions show periodical fluctuations along with the reciprocating movement of the yarn guide plate. In particular, the maximum tension at the initial winding stage has increased 12.6% when compared to the second winding stage, while the maximum tension at the third winding stage has increased 10.6% when compared to the second winding stage.

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Schramm, Laurier L., and Loren G. Hepler. "Surface and interfacial tensions of aqueous dispersions of charged colloidal (clay) particles." Canadian Journal of Chemistry 72, no. 9 (September 1, 1994): 1915–20. http://dx.doi.org/10.1139/v94-243.

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We have measured (du Nouy ring and maximum bubble pressure methods) suspension–air surface tensions of aqueous suspensions of montmorillonite and have observed that these surface tensions are larger than those of pure water at the same temperatures. Further measurements have shown that dispersed montmorillonite also increases the suspension–toluene interfacial tension compared with that of pure water–toluene. Similar measurements on aqueous suspensions of kaolinite have yielded suspension–air interfacial tensions with uncertainties as large as the observed (small) effect, and also shown that the suspension–toluene interfacial tension is decreased (opposite to the effect of montmorillonite) by amounts larger than the experimental uncertainties. Measurements of maximum bubble pressures at different flow rates have provided information about the effect of surface age on observed surface tensions.

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11

Oh, Joo Han, Ji Soon Park, Sung-Min Rhee, and Joo Hyun Park. "Maximum Bridging Suture Tension Provides Better Clinical Outcomes in Transosseous-Equivalent Rotator Cuff Repair: A Clinical, Prospective Randomized Comparative Study." American Journal of Sports Medicine 48, no. 9 (June 18, 2020): 2129–36. http://dx.doi.org/10.1177/0363546520930425.

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Background: Some studies reporting clinical outcomes after transosseous-equivalent (TOE) repair have attributed type II rotator cuff failure to excessive bridging suture tension, as it can cause overloading on the medial row. In a previous biomechanical cadaveric study, increasing bridging suture tension over 90 N did not improve the contact area and ultimate failure load of the TOE construct, despite increasing the contact force and contact pressure. Purpose: To compare the clinical outcomes of different bridging suture tensions after TOE rotator cuff repair based on the results of a previous biomechanical study. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: A total of 78 patients who underwent arthroscopic rotator cuff repair for medium- to large-sized tears were prospectively enrolled and randomly divided into 2 groups according to the applied bridging suture tension: optimum tension group (96.3 ± 4.9 N) and maximum tension group (199.0 ± 20.3 N). Bridging suture tension was measured with a customized tensiometer, as used in the previous biomechanical study. The functional outcome was measured at the final follow-up (27.4 ± 5.9 months [range, 24-45 months]) using the visual analog scale for pain, American Shoulder and Elbow Surgeons score, Simple Shoulder Test, and Constant score, and the anatomic outcome was evaluated using magnetic resonance imaging or ultrasonography at least 12 months after surgery. Results: Overall, 64 patients (32 in each group) were analyzed. The functional outcomes improved significantly compared with preoperative values (all P < .05) but did not show significant differences between the 2 groups (all P > .05). Regarding the anatomic outcomes, the maximum tension group (n = 1; 3.1%) had a significantly lower healing failure rate than the optimum tension group (n = 9; 28.1%) ( P = .013). One patient in the maximum tension group had a type II failure. Conclusion: Maximum bridging suture tension in TOE repair for medium- to large-sized rotator cuff tears provided better anatomic healing with less risk of medial rotator cuff failure, which differs from the results of a previous time-zero biomechanical study.

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12

JOSEPH, DANIEL D. "Cavitation and the state of stress in a flowing liquid." Journal of Fluid Mechanics 366 (July 10, 1998): 367–78. http://dx.doi.org/10.1017/s0022112098001530.

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The problem of the inception of cavitation is formulated in terms of a comparison of the breaking strength or cavitation threshold at each point in a liquid sample with the principal stresses there. A criterion of maximum tension is proposed which unifies the theory of cavitation, the theory of maximum tensile strength of liquid filaments and the theory of fracture of amorphous solids. Liquids at atmospheric pressure which cannot withstand tension will cavitate when and where tensile stresses due to motion exceed one atmosphere. A cavity will open in the direction of the maximum tensile stress which is 45° from the plane of shearing in pure shear of a Newtonian fluid. Experiments which support these ideas are discussed and some new experiments are proposed.

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13

Nathanail, Antonios, Elias R. Most, and Luciano Rezzolla. "GW170817 and GW190814: Tension on the Maximum Mass." Astrophysical Journal Letters 908, no. 2 (February 1, 2021): L28. http://dx.doi.org/10.3847/2041-8213/abdfc6.

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14

Marichev, V. A. "Maximum surface tension and optimum surface electron density." Colloids and Surfaces A: Physicochemical and Engineering Aspects 389, no. 1-3 (September 2011): 63–68. http://dx.doi.org/10.1016/j.colsurfa.2011.08.050.

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15

Barrow, John D., and G. W. Gibbons. "Maximum tension: with and without a cosmological constant." Monthly Notices of the Royal Astronomical Society 446, no. 4 (December 9, 2014): 3874–77. http://dx.doi.org/10.1093/mnras/stu2378.

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16

Pu, Cheng, Fengyin Liu, and Shaohan Wang. "Liquid Force and Rupture Distance between Two Particles." Advances in Materials Science and Engineering 2021 (August 18, 2021): 1–9. http://dx.doi.org/10.1155/2021/3542686.

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The study of liquid force has a special meaning to industrial manufacturing. By taking the liquid bridges between equal and unequal particles as objects, the liquid force-displacement curves were measured and recorded by using a novel Nano UTM T150 tensile system. The influences of diameter, diameter ratio, liquid volume, and the surface tension on the liquid force-distance curve, the maximum liquid force, and rupture distance were compared and sorted. The results show that the maximum liquid force and rupture distance both increase with the increase in liquid volume, particle diameter, diameter ratio, and surface tension. The diameter plays a decisive role in determining the value of the maximum liquid force compared with surface tension and liquid volume, which only influence the force value in a local range. The rupture distance shows a positive correlation with liquid volume and surface tension and a negative correlation with the diameter or diameter ratio. The maximum liquid force between unequal particles is about half of the sum of the force between the equal spheres of larger and smaller size in that system.

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17

Liu, G., J. M. Toguri, and N. M. Stubina. "Surface tension and density of the molten LaCl3–NaCl binary system." Canadian Journal of Chemistry 65, no. 12 (December 1, 1987): 2779–82. http://dx.doi.org/10.1139/v87-462.

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The surface tension and density of the LaCl3–NaCl system were determined as a function of temperature by the maximum bubble pressure technique. The surface tension and density were found to vary linearly with temperature (1123 < T < 1248 K). At constant temperature, the surface tensions of LaCl3–NaCl melts showed a small negative deviation from Guggenheim's Equation.

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18

Jowsey, Aden, and Matt Visser. "Counterexamples to the Maximum Force Conjecture." Universe 7, no. 11 (October 27, 2021): 403. http://dx.doi.org/10.3390/universe7110403.

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Dimensional analysis shows that the speed of light and Newton’s constant of gravitation can be combined to define a quantity F*=c4/GN with the dimensions of force (equivalently, tension). Then in any physical situation we must have Fphysical=fF*, where the quantity f is some dimensionless function of dimensionless parameters. In many physical situations explicit calculation yields f=O(1), and quite often f≤1/4. This has led multiple authors to suggest a (weak or strong) maximum force/maximum tension conjecture. Working within the framework of standard general relativity, we will instead focus on idealized counter-examples to this conjecture, paying particular attention to the extent to which the counter-examples are physically reasonable. The various idealized counter-examples we shall explore strongly suggest that one should not put too much credence into any truly universal maximum force/maximum tension conjecture. Specifically, idealized fluid spheres on the verge of gravitational collapse will generically violate the weak (and strong) maximum force conjectures. If one wishes to retain any truly general notion of “maximum force” then one will have to very carefully specify precisely which forces are to be allowed within the domain of discourse.

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Arizona, Rafil, Teguh Wibowo, Indarto Indarto, and Deendarlianto Deendarlianto. "The effects of surface tension on the spreading ratio during the impact of multiple droplets onto a hot solid surface." MATEC Web of Conferences 197 (2018): 08016. http://dx.doi.org/10.1051/matecconf/201819708016.

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The impact between multiple droplets onto hot surface is an important process in a spray cooling. The present study was conducted to investigate the dynamics of multiple droplet impact under various surface tensions. Here, the ethylene glycol with compositions of 0%, 5%, and 15% was injected through a nozzle onto stainless steel surface as the multiple droplet. The solid surface was heated at the temperatures of 100 °C, 150 °C, and 200 °C. To observe the dynamics of multiple droplets, a high speed camera with the frame rate of 2000 fps was used. A technique of image processing was developed to determine the maximum droplet spreading ratio. As the result, the surface tension contributes significantly to maximum spreading ratio. As the droplet surface tension decreases, the maximum spreading ratio increases. The maximum spreading ratio appears when the percentage of the ethylene glycol is 15% at the temperature of 150°C. From the visual observation, it is shown that a slower emergence of secondary droplets (droplet splashing) is carried out under a lower surface tension. Hence, surface tension plays an important role on the behavior of emerging secondary droplets. Furthermore, results of the experiments are useful for the validation of available previous CFD models.

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Ju, Dong Ying, J. G. Wang, and Minoru Abe. "In Situ Stress Measurement Method Based on X-Ray Diffraction under Biaxial Tensile Loading." Materials Science Forum 675-677 (February 2011): 615–18. http://dx.doi.org/10.4028/www.scientific.net/msf.675-677.615.

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The purpose of this investigation is to detect damage from stress distribution in the surface of near pre-crack tip by using X-ray diffraction technique during biaxial tension test. An measurements apparatus to measure stress distribution along pre-crack direction was fabrication by use of a biaxial tensile test device and a stress analyzer based on single exposure technique with one position sensitive proportional counter. Stress distribution with different tensile applied stress ratios were measured during biaxial tension test. As results, the shape of actual stress was keeping increase with increasing tensile applied stress. At maximum applied stress, the residual stress increases with the increasing distance from the crack tip; after reaching a maximum it gradually diminish.

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Deng, Yong Sheng, Yong Zhang, Tao Zhou, and Yong Sheng Zhou. "Research of Line-Friction Multi Driving Belt Conveyor." Advanced Materials Research 716 (July 2013): 638–42. http://dx.doi.org/10.4028/www.scientific.net/amr.716.638.

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On the basis of analyzing the line friction belt conveyor transmission mechanism of driving forces, the calculation method of driving force, as well as the design essentials of this conveyor system were pointed out. According to the conditons that the line friction drive motor power, the driving belt tensile strength and its minimum tension, the calculation formula of transmission belt length were obtained respectively. Meanwhile according to the maximum tension that supporting belt permitted, the position of the driving belt would be confirmed. Line friction driving mode may reduce the conveyor belt maximum tension, that is, the belt with a lower intensity levels could be selected, thereby the cost of conveying belt would be greatly reduced.

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Fujisawa, T., T. Utigard, and J. M. Toguri. "Surface tension and density of the molten PbCl2–KCl–NaCl ternary system." Canadian Journal of Chemistry 63, no. 5 (May 1, 1985): 1132–38. http://dx.doi.org/10.1139/v85-192.

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The maximum bubble pressure method was used to determine the surface tension and density of melts within the PbCl2–KCl–NaCl system. The temperature range of this study was from 450 to 800 °C. In all cases, the surface tension was found to decrease with increasing temperature. At constant molar ratios of KCl to NaCl, a minimum in the surface tension was observed at approximately 40 mol% PbCl2. The ternary surface tension values were found to obey the simple additivity expression of the binary surface tensions of PbCl2–KCl and PbCl2–NaCl. Based on these findings, constant surface tension contours have been drawn.The density obtained in the present study agree well with the previously determined densities using a bottom-balance Archimedean technique reported by this laboratory.

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Nguyen, Van Tinh. "Effect of pre-tensioned rope tensions on a ladder structure of turntable ladders." Journal of Science and Technology in Civil Engineering (STCE) - HUCE 16, no. 1 (January 26, 2022): 138–51. http://dx.doi.org/10.31814/stce.huce(nuce)2022-16(1)-12.

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To expand the operating zone and control more precisely, it is vital to enhance the flexural stiffness of the ladder structures of turntable ladders. Based on one set of optimized 3-segment ladders, the author proposed a solution to increase the bending stiffness on each ladder while their mass hardly increases. Steel wire ropes are suggested to be added inside the handrails. They are pre-stretched and controlled to reduce the vertical displacement and rapidly quench oscillation at the ladder top. These benefits have been demonstrated in the dynamic aspect in other works. In this study, the effect of pre-tensioned rope tensions on ladder structure is investigated and evaluated according to current standards. The work includes modeling the ladder structure, defining loads, combining loads, investigating stresses and displacements according to the tension values. Afterward, the positive effects and negative influences, as well as the recommendations on tension load and tensile process, are presented. According to the obtained results, the structure still ensures the working conditions while the tension value reaches the maximum one. Most of the stress values in the structural elements decrease with increasing tension. The vertical displacement at the top decreases significantly.

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Du, Yong Qiang, Jian Zheng, and Jun Hui Yin. "Macroscopic and Microscopic Mechanical Properties of HTPB Coating in Solid Rocket Motor under Cyclic Tension." Key Engineering Materials 842 (May 2020): 10–15. http://dx.doi.org/10.4028/www.scientific.net/kem.842.10.

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Hydroxyl-terminated polybutadiene (HTPB) coating is continuously affected by environment/load spectrum during storage, and its macro and micro mechanical properties will deteriorate. Therefore, the cyclic tension test of HTPB coating was carried out with the elongation of HTPB coating was 5%, 10% and 15%, the tensile rate was 50mm/min, 100mm/min and 500mm/min, respectively, and the tensile times was 1000, and the macro and micro mechanical properties of the samples after cyclic tension were tested. The results show that the maximum stress that can be reached by each cyclic tension decreases with the increase of cyclic times, which proves that stress relaxation occurs. After cyclic tension, the tensile strength and cross-linking density of HTPB coating decrease with the increase of elongation and raise with the increase of tensile rate. There is a good linear correlation between cross-linking density and tensile strength.

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Sagatun, Svein Ivar, Finn Gunnar Nielsen, Erling Handal, and Nils Veland. "Mooring line tension observed through a maximum entropy spectrum." Journal of Marine Science and Technology 4, no. 2 (November 20, 1999): 68–75. http://dx.doi.org/10.1007/s007730050008.

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26

Yang, Jinlong, Joseph M Michaud, Steven Jansen, H. Jochen Schenk, and Yi Y. Zuo. "Dynamic surface tension of xylem sap lipids." Tree Physiology 40, no. 4 (February 6, 2020): 433–44. http://dx.doi.org/10.1093/treephys/tpaa006.

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Abstract The surface tension of xylem sap has been traditionally assumed to be close to that of the pure water because decreasing surface tension is thought to increase vulnerability to air seeding and embolism. However, xylem sap contains insoluble lipid-based surfactants, which also coat vessel and pit membrane surfaces, where gas bubbles can enter xylem under negative pressure in the process known as air seeding. Because of the insolubility of amphiphilic lipids, the surface tension influencing air seeding in pit pores is not the equilibrium surface tension of extracted bulk sap but the local surface tension at gas–liquid interfaces, which depends dynamically on the local concentration of lipids per surface area. To estimate the dynamic surface tension in lipid layers that line surfaces in the xylem apoplast, we studied the time-dependent and surface area-regulated surface tensions of apoplastic lipids extracted from xylem sap of four woody angiosperm plants using constrained drop surfactometry. Xylem lipids were found to demonstrate potent surface activity, with surface tensions reaching an equilibrium at ~25 mN m-1 and varying between a minimum of 19 mN m-1 and a maximum of 68 mN m-1 when changing the surface area between 50 and 160% around the equilibrium surface area. It is concluded that xylem lipid films in natural conditions most likely range from nonequilibrium metastable conditions of a supersaturated compression state to an undersaturated expansion state, depending on the local surface areas of gas–liquid interfaces. Together with findings that maximum pore constrictions in angiosperm pit membranes are much smaller than previously assumed, low dynamic surface tension in xylem turns out to be entirely compatible with the cohesion–tension and air-seeding theories, as well as with the existence of lipid-coated nanobubbles in xylem sap, and with the range of vulnerabilities to embolism observed in plants.

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Nascimento, Joycilene Teixeira do, Maria do Bom Concelho Lacerda Medeiros, Joaquim Alves de Lima Júnior, Helane Cristina Aguiar Santos, and Pedro Daniel de Oliveira. "Effect of different soil water tensions and potassium fertilization on the production and quality of netted melon (cucumis melo l.) in the Amazon area." April 2022, no. 16(04):2022 (April 1, 2022): 441–47. http://dx.doi.org/10.21475/ajcs.22.16.04.p3137.

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The objective of this study was to evaluate the production and qualitative behavior of netted melon in a protected environment subjected to different soil water tensions and potassium doses, applied via fertigation. The experimental design was randomized blocks (RBD) in a 4 x 5 factorial scheme with 20 treatments and three replicates, consisting of five percentage doses of potassium (0, 50, 100, 150 and 200%) and four soil water tensions (15, 30, 45 and 60 kPa). The variables analyzed were average yield (t ha-1), transverse and longitudinal diameter of fruits (mm), pulp thickness (mm), °Brix (%) and pH. Yield and fruit longitudinal diameter were decreased linearly with the increase in soil water tension. The best result for yield and fruit longitudinal diameter of 51.24 t ha-1 and 127.7 mm were achieved, respectively, when irrigation performed at 15 kPa tension. The lowest value was found at the maximum tension (60 kPa). Regarding potassium doses, a quadratic model fitted to the data, with maximum values of yield and longitudinal diameter at the K2O doses of 235.30 and 232.82 kg ha-1, respectively. The interaction of T x K led to higher values of °Brix under 247.68 and 371.52 kg ha-1 of K2O with tension of 24.67 kPa, with no difference between both. The best result of fruit transverse diameter was observed under combination of 371.52 kg ha-1 of K2O and 15 kPa tension. Irrigation at tension of 15 kPa and K2O dose of 247.68 kg ha-1 can be indicated for the study conditions

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Piccolo, Lara, and Kathrin Kienapfel. "Voluntary Rein Tension in Horses When Moving Unridden in a Dressage Frame Compared with Ridden Tests of the Same Horses—A Pilot Study." Animals 9, no. 6 (June 6, 2019): 321. http://dx.doi.org/10.3390/ani9060321.

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Too much rein tension while riding may compromise the welfare of the horse. But who generates the tension on the reins—the horse or the rider? The primary aim of this pilot study was to evaluate the maximum rein tension that horses voluntarily maintain without a rider compared to rein tension with a rider. A secondary aim was to evaluate conflict behaviours in relation to rein tension. Thirteen horses were used, all fitted with customised “Animon” rein tension sensors (25 Hz, up to 600 N range), free-moving with side reins set in dressage competition frame with the noseline on the vertical. Rein tension was measured at the walk, trot, and canter in both directions in a round pen. The same horses were then ridden by their usual riders and completed the same task on a riding ground. Continuous video recordings were obtained to subsequently quantify the occurrence of conflict behaviours. The difference in mean maximum peak of rein tension with and without a rider for each gait was compared using the Wilcoxon Rank Sum test. Without a rider, rein tension was significantly lower (Wilcoxon T = 0, p < 0.01, 7.5 N ± 2.8 N) than with a rider (Wilcoxon T = 0, p < 0.01, 24.0 N ± 12.3 N). Regardless of the different rein tensions in the ridden exercise, all of the horses exhibited approximately the same amount of rein tension in the unridden exercise. The frequency of conflict behaviour was higher with a rider than without (11 ± 14 per minute vs. 2 ± 3 per minute; T = 4, p < 0.01).

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Lotsberg, I. "Probabilistic Design of the Tethers of a Tension Leg Platform." Journal of Offshore Mechanics and Arctic Engineering 113, no. 2 (May 1, 1991): 162–70. http://dx.doi.org/10.1115/1.2919913.

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Probabilistic design of the tethers of a tension leg platform is described. It is used to determine the maximum and minimum tension in tethers for the intact condition. The reliability of the tethers for maximum and minimum tension when one tether is missing has been calculated. Also, the reliability of maximum and minimum tension in the tethers as a function of flooding of a corner column has been calculated.

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30

Igarashi, Kazuo, Koji Tajiri, Tadashi Asashina, Mineo Kosaka, Yasuhiko Iwadate, and Junichi Mochinaga. "Surface Tension Around Eutectic Compositions of Molten Alkali Carbonate Mixtures." Zeitschrift für Naturforschung A 47, no. 5 (May 1, 1992): 675–77. http://dx.doi.org/10.1515/zna-1992-0506.

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Abstract The surface tension around the eutectic composition of molten binary and ternary mixtures composed of Li2CO3 with Na2CO3 and/or K2 CO3 has been measured by the maximum bubble pressure method. The surface tensions of all the three systems were represented as functions of temperature

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He, Fan, Dandan Guo, and Liming Chen. "Numerical study of contact wire tension affecting dropper stress of a catenary system." Advances in Mechanical Engineering 13, no. 3 (March 2021): 168781402199504. http://dx.doi.org/10.1177/1687814021995041.

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Dropper is the key component of in a catenary system and it is prone to fatigue fracture. Dropper stress directly affects the operation safety of high-speed railway. In this paper, a span of dropper in a catenary system is modeled to investigate the effects of contact wire tension on dropper stress. The response equation of contact wire and the theoretical equation of dropper stress are deduced. The initial and boundary conditions of each dropper are determined, and then the stress of each dropper is calculated by the finite difference method using a MATLAB program. The results show that the stress amplitude and the maximum tensile stress of the dropper decrease significantly with the increase of contact wire tension. When the tension is low, the stress changes of dropper near the load location experience three stages: instant rebound, attenuated vibration, and bending compression. However, the attenuation vibration stage disappears when the tension is increased to a certain extent. Therefore, the control of the vibration response of the contact wire can effectively reduce the stress amplitude and the maximum tensile stress of the dropper, so as to improve the working reliability of the dropper.

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Botterman, B. R., and T. C. Cope. "Maximum tension predicts relative endurance of fast-twitch motor units in the cat." Journal of Neurophysiology 60, no. 4 (October 1, 1988): 1215–26. http://dx.doi.org/10.1152/jn.1988.60.4.1215.

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1. The relationships between maximum tetanic tension (P0), endurance time, and axonal conduction velocity (CV) were investigated in fast-twitch motor units of the cat flexor carpi radialis (FCR) and medial gastrocnemius (MG) muscles, and in one flexor digitorum longus (FDL) muscle. Endurance time was the length of time that a unit could maintain 25% of its maximum tetanic tension during a sustained contraction. Motor-unit tension was "clamped" at 25% of maximum by altering the stimulation rate of a unit's motor axon through computer feedback control. 2. In individual experiments, including the one investigated FDL muscle, an inverse relation was consistently found between maximum tension and endurance time. Pooled data from the FCR and MG muscles also resulted in significant correlations between maximum tetanic tension and endurance time. 3. Following the force-clamp contraction, some motor units were subjected to the standard fatigue test of Burke and colleagues (6). Motor units were classified as type FR (fast twitch, fatigue resistant) or type FF* (fast twitch, fast fatiguing after the force-clamp contraction). For both type FR and FF* units, maximum tetanic tension and endurance time were found to be inversely related. However, no correlation was found between maximum tetanic tension and fatigue index for type FR units. Only when all type F (FR + FF*) units were considered as a population was there a significant correlation between these two properties. 4. Other investigators have shown that maximum tetanic tension and axonal conduction velocity are highly correlated with the recruitment order of motoneurons (e.g., Refs. 2, 26). Endurance time was found to be more tightly coupled with contraction strength than with conduction velocity. In 12 of 14 experiments, significant Spearman rank correlation coefficients were found between endurance time and tension, whereas significant correlations were found in only 3 of 14 experiments for endurance time and conduction velocity. 5. Pairs of motor units isolated from the same muscle were formed to see if the unit with the smaller tension had the slower conduction velocity and the longer endurance time. Across all muscles, the probability that the unit with the smallest tension had the greatest endurance time was 0.91 (441 of 487 pairs). By contrast, the probability that the least forceful unit of the pair had the slowest conduction velocity was 0.61. 6. In four experiments, pairs of type-identified units were examined. Among FR-FR pairs, the least forceful unit had the greatest endurance time in 88% of 43 pairs. For FF*-FF* pairs, the percentage was somewhat lower, 72% of 29 pairs.(ABSTRACT TRUNCATED AT 400 WORDS)

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Akita, Hiroshi, Dariusz Alterman, and Hideo Koide. "Size Effect of Concrete in Uniaxial Tension." Advanced Materials Research 41-42 (April 2008): 227–32. http://dx.doi.org/10.4028/www.scientific.net/amr.41-42.227.

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In order to investigate the size effect of concrete, four sizes of rectangular prisms were tested in uniaxial tension. The cross sections of the prisms were 50x100mm, 100x100mm, 200x100mm and 400x100mm. The concrete was an ordinary one with the compressive strength of 34 MPa and the maximum aggregate size of 20mm. Notches were applied on four side faces and secondary flexure was completely eliminated during the test in order to obtain the exact nominal tensile strength. The size effect was analyzed by four factors, namely tensile strength, fracture energy, critical crack opening displacement and tension softening curves. Clear size dependence was observed in critical crack opening displacement and initial convexity of tension softening curves, and a slight size dependence was observed in tensile strength. On the other hand, size effect was unclear in fracture energy and other part of tension softening curves because of their scatters.

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Tryding, Johan, Gustav Marin, Mikael Nygårds, Petri Mäkelä, and Giulio Ferrari. "Experimental and theoretical analysis of in-plane cohesive testing of paperboard." International Journal of Damage Mechanics 26, no. 6 (March 11, 2016): 895–918. http://dx.doi.org/10.1177/1056789516630776.

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In-plane cohesive failure of paperboard was characterized by short-span uniaxial tension tests. Six paperboards' qualities were experimentally investigated, from which cohesive stress–widening curves were extracted. A fracture energy was defined, expressed in the tensile strength and maximum slope of the cohesive stress–widening relation. Analytical cohesive relations were derived based on the tensile strength and maximum slope, utilizing the Morse potential for diatomic molecules. It was experimentally found that the maximum slope and fracture energy depend on the tensile strength. The ratio of the maximum slope to the elastic modulus (stable length) was shown to be independent of the tensile strength.

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McAfee, Joshua R., Kevin J. Shinners, and Joshua C. Friede. "Twine Tension in High-Density Large Square Bales." Applied Engineering in Agriculture 34, no. 3 (2018): 515–25. http://dx.doi.org/10.13031/aea.12606.

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Abstract.When greater density bales are made, baler manufacturers recommend using twine with greater knot strength. When twine fails, bale integrity is lost, harvesting costs increase, and productivity suffers. Twine failure typically occurs in the knot on the top strand of the twine. A better understanding of twine tension in the top strands could help reduce failures, allow for improved knot strength recommendations, and ultimately lower baling costs. A system was developed to measure the tension of the top strands while baling a variety of crops with a high-density large square baler. Depending on the bale chute design, twine tension was greatest as the bale cantilevered from the chamber but had not yet touched the chute or just as the bale fully exited the bale chamber. In either case, the absolute maximum recorded tensions were typically less than 60% of the twine specified knot strength. Pulses in synchronization with the plunger frequency were superimposed on the nominal twine tension. Tension was usually greatest in the outer left twine and the other right twine because for each, there was only one neighboring twine to share the load. Average twine tension over the first 60 s after the bale rested on the ground was linearly related to bale density. Crop stress relaxation reduced tension up to 20% within 20 min after the bale was placed on the ground. Top strand tension approached 60% of knot strength for only a short duration as the bale exited the chamber and after that, the tension was much less than the specified knot strength. Therefore, design changes or strategies that reduce tension during the critical period when the bale exits the chamber could reduce maximum knot strength requirements and lead to lower baling costs. Keywords: Bales, Density, Tension, Twine.

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Jiang, Yin Fang, Zhen Zhou Tang, Zhi Fei Li, and Lei Fang. "Research on the Forming Limit Diagram Based on Laser Shock Forming." Applied Mechanics and Materials 44-47 (December 2010): 148–52. http://dx.doi.org/10.4028/www.scientific.net/amm.44-47.148.

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Laser shock forming (LSF) of sheet metal is a novel technology in plastic deformation. It is necessary to correctly predict the Forming Limit Diagram (FLD) based on LSF. New failure maximum thickness reduction rate criterion is used to determine the forming limit based on the numerical system during LSF. The relationship model between maximum thickness reduction rate and the strain path is built. In addition, the effects of strain path and strain-hardening exponent on forming limit are considered. The maximum thickness reduction rate under equi-biaxial tensile strain path can be determined easily during LSF and the expression of the criterion is determined finally. Then the limit strains under other strain paths between uniaxial tension to equi-biaxial tension can be determined by the criterion combined with numerical simulation of forming process. The criterion can predict forming limits for sheet metal exactly and makes it possible to determine forming limit strains under different strain paths only through equi-biaxial tensile test during LSF.

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Harada, Y., M. Ohmori, and Lei Wang. "Serration Phenomenon in High Purity Chromium." Materials Science Forum 449-452 (March 2004): 269–72. http://dx.doi.org/10.4028/www.scientific.net/msf.449-452.269.

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Serration phenomenon of sintered and cast chromium was investigated by means of tension test at various strain rates. With increasing test temperature, tensile strength decreased gradually at first and showed a minimum at a certain temperature. Above this temperature, the strength continued to increase to a maximum value. Serrated flow appeared between the temperatures of the minimum and maximum tensile strengths. Tensile ductility minimum was also observed around the temperature of the maximum tensile strength. Relation between the strain rate and the temperature T of the maximum tensile strength could be well described by an Arrhenius equation. Activation energy of 101.3kJ/mol found in the present study is in good agreement with the activation energy for diffusion of nitrogen atom in chromium.

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Yang, Mao, Hong Zhang, Jianting Zhou, Hejing Jiang, Yu Zheng, and Jian Qiu. "Magnetic memory detection of corroded reinforced concrete considering the influence of tensile load." International Journal of Applied Electromagnetics and Mechanics 68, no. 4 (April 8, 2022): 483–99. http://dx.doi.org/10.3233/jae-210172.

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Both corrosion defects and stress can cause magnetic field mutations, so the effect of stress must be considered in the magnetic detection of steel corrosion. This paper focuses on exploring the influence law of tension on magnetic signals of the corroded specimens. Based on the spontaneous magnetic leakage mechanism of steel bar corrosion and the stress magnetization model, the magnetic memory detection of corroded reinforced concrete under tension was carried out. The magnetic characteristics of corroded specimens before and after loading were analyzed. The corrosion positions of the specimens can be determined according to the representative mutation points (RMP) of the Byc(0) curves, and the magnetic index I2 was proposed to roughly determine the corrosion degree of the specimens when the specimens were not subjected to tensions. The experimental results showed that the RMP of Byc(F) curves can still represent corrosion positions when the specimens were under tension. The theoretical derivation showed that the magnetic field change caused by tensile force is limited, and the maximum value of the magnetic field change caused by tensile force can be obtained. Based on this, the corresponding I3-F curves were obtained through the test. The magnetic field change caused by the most unfavorable tensions was calculated to analyze its influence on corrosion magnetic detection. Compared with I2, the relationship between I3 and the corrosion degree was more discrete, indicating that tensile forces affected the quantitative detection of corrosion. Still, the magnetic field caused by corrosion played a leading role. The verification showed that the measured corrosion positions of reinforced concrete specimens were in good agreement with those detected by the magnetic memory method.

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Lim, Myunghwan, and Changhee Lee. "Flexural Performance of Reinforced Concrete Members with Steel Bars." Applied Sciences 11, no. 10 (May 15, 2021): 4512. http://dx.doi.org/10.3390/app11104512.

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The use of high-tension bars to strengthen flexural members is gaining increasing interest. However, the applicability of current standards to such bars is uncertain, because there may not be a definite yield strength and it may be unclear whether the tensile or compressive failure mode dominates. Determining the balanced–destruction steel ratio is particularly difficult. We measure the bending behaviour of flexural members containing high-tension bars with different yield strengths and tensile steel ratios. We conclude that the maximum-steel-ratio regulation and nominal -strength equation in the current standard remain applicable.

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Chikhi, N., J. Delacroix, P. Fouquart, and B. Turquais. "Measurement of corium surface tension using the maximum bubble pressure." Nuclear Engineering and Design 379 (August 2021): 111266. http://dx.doi.org/10.1016/j.nucengdes.2021.111266.

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Egenvall, Agneta, Lars Roepstorff, Marie Rhodin, Marie Eisersiö, and Hilary M. Clayton. "Maximum and minimum peaks in rein tension within canter strides." Journal of Veterinary Behavior 13 (May 2016): 63–71. http://dx.doi.org/10.1016/j.jveb.2016.03.007.

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Mysels, Karol J. "The maximum bubble pressure method of measuring surface tension, revisited." Colloids and Surfaces 43, no. 2 (January 1990): 241–62. http://dx.doi.org/10.1016/0166-6622(90)80291-b.

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Gutman, E. M. "Comment on “Maximum surface tension and optimum surface electron density”." Colloids and Surfaces A: Physicochemical and Engineering Aspects 410 (September 2012): 184–85. http://dx.doi.org/10.1016/j.colsurfa.2012.05.040.

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Widing, Mary Ann Bitz, and Manssour H. Moeinzadeh. "Finite Element Modeling of a Tennis Racket with Variable String Patterns and Tensions." International Journal of Sport Biomechanics 6, no. 1 (February 1990): 78–91. http://dx.doi.org/10.1123/ijsb.6.1.78.

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Finite element techniques were applied in a model of a tennis racket. Linear curved elements were used on the frame of the racket. Nonlinear cable elements were used on the strings. The model allows changing material properties and frame geometry, as do traditional models. Unlike traditional models, however, this model has the flexibility to change the string pattern and string tensions, as the strings are modeled discretely. Sample runs revealed information on the relationship between racket parameters and racket behavior such as deformations, stresses, and reaction forces. The results of the model showed that increasing string tension decreases racket deformation as string tension stiffens the racket. Increased string tension also decreases maximum hand reaction forces but increases stresses.

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Watson, M. A., K. J. Mathias, G. P. Ashcroft, N. Maffulli, D. W. L. Hukins, and D. E. T. Shepherd. "Wire Tension in the Ilizarov System: Accuracy of the Wire-Tensioning Device." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 219, no. 5 (May 1, 2005): 355–59. http://dx.doi.org/10.1243/095441105x34310.

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The Ilizarov fixator consists of tensioned wires that attach bone segments to a modular frame. The aim of this study was to establish the accuracy and precision of the wire-tensioning device supplied with the Ilizarov external fixation system. The device was used to tension a wire in direct opposition to a calibrated load cell. Five subjects tested three devices, at each of their four tension settings, in two separate sessions. Subjects could not see the true tension during the test. There were significant differences between the results for different subjects ( p <0.01) and instruments ( p <0.01) but not for different tension settings or between the two sessions. Overall mean measured tensions were 4.9 per cent (standard deviation, 4.4 per cent) below intended values. Tensions obtained at the maximum edge (completely occluded) on the scale markings were significantly ( p <0.001) closer to the nominal values (mean discrepancy, 3.6 per cent) than those at the minimum edge (mean discrepancy, 17.6 per cent). Several factors influence wire tension. Tensioning devices are not identical and the results obtained with them depend on the user. If the scale markings are completely occluded, the discrepancy between intended and actual tensions of around 5 per cent is likely to be adequate for clinical practice since surgeons do not select the most suitable tension following quantitative data assessment, but rather it is a judgement based on surgical experience and consideration for the patient weight and expected level of activity.

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Shi, Qian, and Shou Xi Chai. "Evaluating Anti-Decay Effect of Rice Straw Based on Grey Correlative Method." Advanced Materials Research 146-147 (October 2010): 1270–77. http://dx.doi.org/10.4028/www.scientific.net/amr.146-147.1270.

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Anti-decayed rice straw may be used to reinforce saline soil in inshore of Northern China. Water absorption, maximum elongation and maximum tension of rice straw, including rice straw soaked in seawater, running water and seawater after SH agent has been tested, and anti-decay effect is evaluated based on grey correlative method. The experimental results showed that water absorption of rice straw soaked in seawater and running water increased with soaking time. And maximum elongation and maximum tension decreased with soaking time. The reduction rate of water absorption was the greatest when the rice straw was soaked in seawater after SH agent for 14-day and which had the biggest maximum elongation and maximum tension yet. According to grey correlative method, the relational degrees of water absorption, maximum elongation and maximum tension for 14-day are the biggest. It means that anti-decay effect is the best in this condition. Taking rice straw which soaked in seawater after SH agent for 7-day as example, correlation coefficients of water absorption, maximum elongation and maximum tension increase with soaking time. It indicates that the longer soaking time is, the better anti-decay effect of rice straw is. Evaluating anti-decay effect of rice straw according to grey correlative method and analyzing the laboratory results respectively, they are highly consistent. Grey correlative method is a suitable one for evaluating the anti-decay effect of rice straw.

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47

Emami, Ebrahim, Ali Kheyroddin, and Omid Rezaifar. "Eccentricity and slenderness ratio effects of arched steel haunches subjected to cyclic loading; experimental study." Advances in Structural Engineering 25, no. 6 (February 23, 2022): 1339–56. http://dx.doi.org/10.1177/13694332211063677.

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This paper investigated the cyclic performance of arched steel haunches as a new strategy in the seismic retrofitting of reinforced concrete frames and focused on the slenderness ratio effect. A series of cyclic loading were conducted on six test specimens in two groups with the same nominal length and different axial eccentricities of 0.1 and 0.2 nominal length and with out-of-plane slenderness ratios of 138, 69, and 16. Experimental results indicated that the slenderness ratio played a very important role on cyclic performance in compression and even tension, so that a more desirable hysteretic behavior was achieved when the overall buckling potential was restricted. Therefore, by reducing this ratio, the maximum compressive and tensile strengths increased up to 1.78 and 1.28 times, respectively, and also the dissipated energy and maximum viscous damping upgraded up to 3.32 and 1.43 times, respectively. More difference in tensile and compressive behavior for ultimate strength and plastic stiffness was observed, when the initial eccentricity decreased. Also, with twice increase in the initial eccentricity, the cross-sectional area effect on the maximum strength and plastic stiffness decreased, especially in tension, so that despite the same slenderness ratio and 70% increase in cross-sectional area, these values in tension descended up to 1.31 and 3.5 times, respectively. In addition, the compressive plastic stiffness degraded about 77% due to more degradation in plastic strength.

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Supinski, G. S., H. Bark, A. Guanciale, and S. G. Kelsen. "Effect of alterations in muscle fiber length on diaphragm blood flow." Journal of Applied Physiology 60, no. 5 (May 1, 1986): 1789–96. http://dx.doi.org/10.1152/jappl.1986.60.5.1789.

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A variety of studies have examined the response of diaphragmatic blood flow (Qdi) to rhythmic pleiometric (i.e., shortening) and isometric contractions. The effect of changes in diaphragm fiber length on Qdi are, however, unknown. The present study examined the effect of changes in diaphragm fiber length on Qdi and the effect of alterations in length on the response of Qdi to increases in diaphragm contractile activity. Studies were performed on 21 anesthetized mechanically ventilated dogs in which a strip of costal diaphragm was developed in situ. The strip was immobilized in a rigid metal frame that permitted precise adjustment of muscle length. Strip blood flow was assessed with a drop counter attached to a catheter in the branch of the phrenic vein draining the strip. Strips were electrically stimulated via intramuscular electrodes, and the isometric tension developed was measured with a force transducer. Fiber length was expressed as a percentage of the length at which active isometric tension was maximum (Lo). With the diaphragm at rest, steady-state blood flow fell by 59 +/- 6% (SE) (P less than 0.001) as fiber length was increased from 92 to 107% Lo. Blood flow also varied as a function of length when muscles contracted rhythmically (15 contractions/min, duty cycle 50%) to generate isometric tensions equal to 20 and 80% of maximum. As fiber length increased from 92 to 106% Lo, Qdi fell by 36 +/- 6% (SE) when tension was 80% of maximum (P less than 0.01) and by 38 +/- 6% (SE) when tension was 20% of maximum (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

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49

Hofmann, P. A., V. Menon, and K. F. Gannaway. "Effects of diabetes on isometric tension as a function of [Ca2+] and pH in rat skinned cardiac myocytes." American Journal of Physiology-Heart and Circulatory Physiology 269, no. 5 (November 1, 1995): H1656—H1663. http://dx.doi.org/10.1152/ajpheart.1995.269.5.h1656.

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In diabetes a primary myocardial defect occurs that is characterized by decreases in systolic pressure and cardiac output. The present study investigates whether diabetes causes a decreased maximum tension-generating ability, decreased Ca2+ sensitivity of myofilaments, or no change in cardiac myofilament contractile properties at pH 7.0 and 6.6. Hearts from Wistar rats were excised and mechanically disrupted 6-10 wk after injection of streptozotocin. The resulting myocyte-size preparations of skinned myocardium were used to determine the steady-state tension-negative, log molar Ca2+ concentration (pCa) relation. Maximum tension was unchanged, and the pCa of half-maximum tension generation was 0.14 pCa units lower than control for skinned myocytes from diabetic rats at pH 7.0. A significantly lower than normal maximum tension was observed at pH 6.6 for cardiac myocytes from diabetic rats. Increased expression of beta-myosin heavy chain (MHC) occurred in hearts from diabetic rats. Two troponin T (TnT) isoforms in myocardium of adult rats were identified by Western blots. The ratio of the two TnT isoforms were altered in diabetes. Changes in cardiac MHC and TnT expression may contribute to the observed decrease in Ca2+ sensitivity of myofilaments at pH 7.0 and decreased maximum tension-generating ability at pH 6.6 in diabetes.

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Ruff, R. L., and P. Spiegel. "Ca sensitivity and acetylcholine receptor currents of twitch and tonic snake muscle fibers." American Journal of Physiology-Cell Physiology 259, no. 6 (December 1, 1990): C911—C919. http://dx.doi.org/10.1152/ajpcell.1990.259.6.c911.

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Myofibrillar Ca sensitivity and single-channel acetylcholine receptor (AChR) currents were studied in garter snake (Thamnophis sirtalis sirtalis) costocutaneous muscle fibers. Nomarski optics were used to identify tonic and fast- and slow-twitch fibers. Measurements of tension generation were made using chemically skinned fibers. The maximum tensions of the three types of fibers were similar, and the fast- and slow-twitch fibers had similar Ca sensitivities. Compared with twitch fibers, tonic fibers had lower threshold Ca concentrations for tension generation and a larger range of Ca concentrations between threshold and maximum tension. The AChR channels were studied by enzymatically removing the nerve terminals and performing patch-clamp recordings on the exposed postsynaptic membrane. Twitch fibers had only one class of end-plate channel with a conductance of approximately 51 pS. Tonic fibers had two types of synaptic channels. One AChR channel in the tonic fibers resembled the type seen in twitch fibers. The other channel in tonic fibers had a smaller conductance of approximately 33 pS and resembled extrajunctional AChRs on denervated twitch fibers.

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Journal articles on the topic 'Maximum Tension'

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