The Effect of Movement Speed Exercises in Learning the Skills of Rolling and Controlling Soccer for Players Aged 15 Years

The aim of the research is to prepare skill with restrictive rubber bands for football players of 15 years of age. As well as learning about the effect of these exercises on improving the skills of rolling and controlling football for players aged 5 years. The research sample was conducted by the players of the National Center for the Care of Sports Talent in Football. They were divided into two equal experimental groups, one of which is subject to special training and the other is left for regular training. (8) Weeks, two training units per week, and after that the post-tests were conducted, and the researchers reached skill training with tied ligaments that positively affected the development of the ball control skill and the ball rolling skill. Also, the use of exercises developed by the researcher and developed in a manner consistent with the capabilities of the players and their ages.

Abrasive Wear, Scuffing and Rolling Contact Fatigue of DLC-Coated 18CrNiMo7-6 Steel Lubricated by a Pure and Contaminated Gear Oil

Due to extreme working conditions of mining conveyors, which contaminate gear oil with solid particles, their transmissions are exposed to intensive abrasion, scuffing, and even rolling contact fatigue (pitting). These effects shorten gear life. To prevent their occurrence, a wear-resistant coating can be deposited on gear teeth. The resistance to abrasive wear, scuffing, and pitting was investigated and reported in the article. Simple, model specimens were used. Abrasive wear and scuffing were tested using a pin-and-vee-block tribosystem in sliding contact. A cone–three-ball rolling tribosystem was employed to test pitting. The material of the test specimens (pins, vee blocks, cones) was 18CrNiMo7-6 case-hardened steel. Two types of DLC (Diamond-like Coatings) coatings were tested, W-DLC and W-DLC/CrN. The vee blocks and cones were coated. Two industrial gear oils were selected to lubricate the specimens: one with a mineral and one with a synthetic PAO (polyalphaolephine) base, as pure oil or contaminated with solid particles from a coal mine. The results show that, to minimize the tendency to abrasion, scuffing, and pitting of specimens made of 18CrNiMo7-6 steel, the W-DLC/CrN coating should be deposited. This coating also gives very good protection when the lubricating oil is contaminated.

Human Rights Litigation against Multinationals in Practice

Daniel Leader reviews multinational human rights cases that have developed English law on jurisdiction and parent company liability. He considers the first batch of parent company cases that started the ball rolling in the 1990s, leading to the establishment of the parent company duty of care principle in Chandler v. Cape. He explains the principles of the 2019 and 2021 Supreme Court decisions in Lungowe v. Vedanta and Opkabi v. Shell, and the first trial of a parent company case, where an international auditor was found in breached of its duty to act ethically. The key principles developed on jurisdiction and forum non conveniens are explained. He reviews security and human rights cases, including recent settlements against Gemfields and Kakuzi. He also reviews supply chain cases arising from shipbreaking and child labour on Malawian tobacco farms. Procedural and practical issues concerning discovery, group actions, witness anonymity, and funding and viability of cases are outlined.

Self- concentrated mass-transfer during deformation treatments of organic-inorganic compositions

This paper prolongs the series of our previous papers where we found super-fast and super-deep introduction of foreign substances in crystalline materials by means of the ball rolling. A set of new experimental results was used to justify the new version of the mechanism of this introduction with the record speed and depth. The main process which determines this phenomena is connected with the sequence of openings and closings of nanocracks at the surface subjected to the rolling and the capture of the substance introduced from the surface by these cracks. The process of this introduction with the record parameters is supported by the intense chemical interactions between the matrix and the substance being introduced. This chemical interaction is intensified by several times with the deformation treatments. The analogous super-fast mass transfer is observed in the situation of the pulling out of the polystyrene fibers from the solution of polystyrene in benzene when the interaction of the organic components with cesium iodide nanoparticles was activated by the deformation treatment of the solution during its pulling out resulting in the formation of big amounts of nano-channels promising for effective utilization of hazardous radioactive wastes.