Superiority In Strength Research Articles

Experimental investigation on the properties of SCC containing metakaolin and polypropylene fibre

Manufacturing of cement causes significant ecological damage in the environment due to the release of CO2 gas, substitute cementitious substances such as finely crushed solid ingredients could be utilized to compensate a percentage of the cement in a concrete mix to reduce the cement’s adverse effects. This paper mainly reports on Mechanical properties of concrete made of Metakaolin and GGBS as partial replacement to cement, Metakaolin dosage was 10–30% with an interval of 10%, whereas GGBS content was kept constant 10% as partial replacement to cement by weight for an M25 Grade Self Compacting Concrete, for optimum strength achieved under compression for a dosage of Metakaolin, Polypropylene fibres were added from 0.2 to 0.8%. Mechanical properties for concrete were studied by conducting various trials like compressive, split tensile and flexural strengths. Superiority in strength was noted at 20% dosage of Metakaolin and 0.4% of Polypropylene fibres.

Periodization: What is it good for?

Resistance training increases muscle size and strength and is associated with numerous health benefits. For many, periodization serves as the cornerstone of programming for resistance training and is commonly touted in the literature as a superior method of training. Objective: To review the literature on the effects of periodization for those looking to improve muscle size and strength. Design and Methods: Non-systematic review. Research articles were collected using search terms such as linear periodization, non-linear periodization, non-periodized, undulating periodization, and strength training models. Results: Previous research has found no differences in muscle size between periodized and non-periodized training programs. Further, there are conflicting reports on what periodized program is superior for increasing muscle strength. It is our contention that the proposed superiority in strength with periodized programs is often explained by the principle of specificity. Conclusion: The use of a periodized program may be advantageous for an athlete in certain sports due to practice and competi tions throughout the season. However, we wish to suggest that the proposed benefits of periodization for those only interested in increasing muscle size and strength are largely founded in conjecture and that there is little compelling evidence that periodization is a superior method of training.

A new hole-flanging method for thick plate by upsetting process

Flange height and lip accuracy are generally restricted by the formability of sheet metals in the conventional hole-flanging operation. A new hole-flanging process, named upsetting-flanging process, was proposed to obtain a more substantial flange from thick plate. The finite element method (FEM) with DEFORM was utilized to simulate the novel upsetting–flanging process and the influence of geometric parameters on the flange height was studied in details. A series of flanging experiments with A1050P-O were carried out to validate the FEM results, and the variations of Vicker hardness in the plate section were discussed. The results showed that the newly upsetting–flanging process revealed higher flange height and better lip accuracy than the conventional hole-flanging process, and the results between FEM simulations and experiments showed good agreement. Besides, the hardness of the plate around the flange part increases due to the work hardening after the upsetting-flanging process, which reveals better superiority in strength for the subsequent machining or assembling processes.

Mechanical properties of unirradiated and irradiated reduced-activation martensitic steels with and without nickel compared to properties of commercial steels

Tensile and Charpy specimens of four normalized-and-tempered martensitic steels were irradiated to 23–33 dpa at 376–405 °C in the Experimental Breeder Reactor (EBR-II). The steels were the ORNL reduced-activation steel 9Cr–2WVTa and that containing 2% Ni (9Cr–2WVTa–2Ni), modified 9Cr–1Mo (9Cr–2WVTa), and Sandvik HT9 (12Cr–1MoVW). Two tempering conditions were used for 9Cr–2WVTa and 9Cr–2WVTa–2Ni: 1 h at 700 °C and 1 h at 750 °C. The 9Cr–1MoVNb and 12Cr–1MoVW were tempered 1 h at 760 °C. These heat treatments produced tempered-martensite microstructures for all steels except 9Cr–2WVTa–2Ni tempered at 750 °C, where a duplex structure of tempered and untempered martensite formed. Based on changes in tensile and Charpy impact properties, the results demonstrated the superiority in strength and ductility of the 9Cr–2WVTa reduced-activation steel over the commercial steels. Comparison of the mechanical properties after irradiation of 9Cr–2WVTa–2Ni and 9Cr–2WVTa steels indicated a favorable effect of nickel that could lead to development of a heat treatment for improved irradiation resistance.

Effectiveness of Reconstruction of the Anterior Cruciate Ligament with Quadrupled Hamstrings and Bone-Patellar Tendon-Bone Autografts

Background The 2 most frequently used autografts for anterior cruciate ligament reconstruction are the bone-patellar tendon-bone and the quadrupled hamstrings tendon. Hypothesis Hamstring tendon graft is superior to patellar tendon graft in restoring tibial rotation during highly demanding activities because of its superiority in strength and linear stiffness and because it is closer morphologically to the anatomy of the natural anterior cruciate ligament. Study Design Case control study; Level of evidence, 3. Methods Eleven patients with patellar tendon graft anterior cruciate ligament reconstruction, 11 patients with hamstring tendon graft anterior cruciate ligament reconstruction, and 11 controls were assessed. Kinematic data were collected (50 Hz) with a 6-camera optoelectronic system while the subjects descended stairs and, immediately after, pivoted on their landing leg. The dependent variable examined was the tibial internal-external rotation during pivoting. All patients in both groups were also assessed clinically and with the use of a KT-1000 arthrometer to evaluate anterior tibial translation. Results The results demonstrated that reconstructions with either graft successfully restored anterior tibial translation. However, both anterior cruciate ligament reconstruction groups had significantly increased tibial rotation when compared with the controls, whereas no differences were found between the 2 reconstructed groups. Conclusion The 2 most frequently used autografts for anterior cruciate ligament reconstruction cannot restore tibial rotation to normal levels. Clinical Relevance New surgical techniques are needed that can better approximate the actual anatomy and function of the anterior cruciate ligament.

Effectiveness of Reconstruction of the Anterior Cruciate Ligament with Quadrupled Hamstrings and Bone-Patellar Tendon-Bone Autografts

Background The 2 most frequently used autografts for anterior cruciate ligament reconstruction are the bone-patellar tendon-bone and the quadrupled hamstrings tendon. Hypothesis Hamstring tendon graft is superior to patellar tendon graft in restoring tibial rotation during highly demanding activities because of its superiority in strength and linear stiffness and because it is closer morphologically to the anatomy of the natural anterior cruciate ligament. Study Design Case control study; Level of evidence, 3. Methods Eleven patients with patellar tendon graft anterior cruciate ligament reconstruction, 11 patients with hamstring tendon graft anterior cruciate ligament reconstruction, and 11 controls were assessed. Kinematic data were collected (50 Hz) with a 6-camera optoelectronic system while the subjects descended stairs and, immediately after, pivoted on their landing leg. The dependent variable examined was the tibial internal-external rotation during pivoting. All patients in both groups were also assessed clinically and with the use of a KT-1000 arthrometer to evaluate anterior tibial translation. Results The results demonstrated that reconstructions with either graft successfully restored anterior tibial translation. However, both anterior cruciate ligament reconstruction groups had significantly increased tibial rotation when compared with the controls, whereas no differences were found between the 2 reconstructed groups. Conclusion The 2 most frequently used autografts for anterior cruciate ligament reconstruction cannot restore tibial rotation to normal levels. Clinical Relevance New surgical techniques are needed that can better approximate the actual anatomy and function of the anterior cruciate ligament.

Rethinking the Concept of Strength

Against the background of the current debate on conventional versus alternative approaches to—and evaluation of—induced development programs, this article challenges the superiority of strength by means of practical illustrations from the field of cooperatives. Analysis of various cooperative projects involving the mentally disabled, poor farmers, and political refugees suggests that the “weak-low” elements of a given situation may include the protential for the participatory change sought, rather than a weakness and a hindrance to the attainment of the same.

Benzoylation of Cotton in Relation to Its Properties

Yarn spun from Indian cotton was partially benzoylated to three low DS values, averaging from 0.2 to 0.6, to retain the fibrous structure and other desirable properties of cotton. Benzoylation of the cotton yarn was carried out in both stretched condition to maintain the original length and unstretched condition to permit free contraction. The changes in physical properties in most cases were affected by the DS and tensional forces on the yarn during modifi cation. The benzoylated cotton yarn retained many of the desirable mechanical properties of the original cotton. It showed increases in linear density, yarn diameter, elongation at break, wet strength, coefficient of friction, and resistance to micro-organisms, but decreases in tensile strength, loss of strength on oven drying and moisture regain, while retaining tensile strength after cyclic loading. Stretched yarn exhibited superiority in strength over unstretched yarn.