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With the rapid development of China's manufacturing industry, products are changing toward better energy efficiency and precision. Reducing transmission energy waste, enhancing transmission lubrication, and increasing transmission efficiency have all become critical concerns. The moving particle semi-implicit particle approach is utilized in this study to create a high-speed rotating meshing gear lubrication model and conduct a simulation analysis of transmission gears by studying the influence law of sensitive parameter injection diameter on lubrication. The oil distribution state on the gear surface, the gear tooth surface heat dissipation effect, and the degree of gear operating stability are all calculated by computing the gear surface fluid coverage and convective heat transfer coefficient. According to the numerical simulation results, increasing the liquid injection diameter can greatly enhance fluid coverage and convective heat transfer coefficient on the gear surface, hence improving lubrication. However, when the injection diameter reaches a critical value, the contact area between the liquid and the gear is maximized, and additional increases in the injection diameter will not improve the lubricating effect. Experiments have revealed that the liquid injection diameter is the most critical factor influencing gears. The gear torque dramatically increases as the liquid injection diameter increases. According to a rigorous analysis, the gear lubrication effect is optimal when the liquid injection diameter is 2.0 mm. This provides a theoretical foundation for transmission system lubrication design. [ABSTRACT FROM AUTHOR]

HIV postexposure prophylaxis (PEP) has been prescribed to non-occupational people in recent years, but the implementation of PEP in China is still unclear. This study sought to examine the PEP use rate and factors associated with PEP in Men who have sex with men (MSM). We recruited HIV-negative MSM through offline methods from 2018 to 2020 in Shenzhen, China. Overall, PEP use increased from 3.92% to 2018, 5.73% in 2019, and 10.29% in 2020. Among 2833 participants who reported their most recent questionnaire, factors associated with PEP use included residence in Shenzhen less than 1 year, sexual intercourse with women, preferred way of finding sexual partners in MSM venues, multiple sexual partners (≥ 2), condom use, lubricant use, viagra use, less use of rush popper, HIV-related services and interest in initiating Pre-exposure prophylaxis (PrEP). The implementation of the PEP plan should focus on the groups that may be at risk of HIV infection and their continued risky behaviours. For the inappropriate use of PEP, PEP publicity should guide MSM to choose regular hospitals and strengthen HIV testing before and after PEP. [ABSTRACT FROM AUTHOR]

The electric discharge bases of the technological advantages of diamond spark grinding make it possible to consider this processing method among the environmentally promising in nature. A decrease in the thermo-mechanical tension of mass micro-cutting in the zone of diamond spark grinding, which is ensured by the development of its working relief, supported by the action of electric discharges on the bond of the wheel, also makes it possible to consider approaches to organizing this process using the minimum lubrication methodology. The paper presents and summarizes the experimental results of using a number of solid lubricants, gives practical recommendations and defines the tasks of further research. Work in this direction is focused on reducing the use of water in servicing industrial needs, which is an urgent global environmental challenge to the development of civilization and meets the modern technocratic strategies of the European Union (Industry 4.0), Japan (Society 5.0), China (Made in China 2025) and other leading world economies. [ABSTRACT FROM AUTHOR]

Water-rock interaction is a vital factor to affect the stabilities of rock projects. This paper conducted a series of experiments on argillaceous limestones to investigate the influences of saturation and wetting-drying cycle on the physical and mechanical performances of rocks. The results show that the increasing saturation increases the dissolution of clay minerals and lubrication among mineral grains, resulting in an obvious reduction effect on the strength and deformation performances of argillaceous limestones. Wetting-drying cycle increases the porosity and changes the pore structure of argillaceous limestones, leading to the pore transformation from small pore (0.01∼0.1 μm) to relatively large pore (0.1∼1.0 μm). Both the physical and mechanical performances of argillaceous limestones are weakened by the wetting-drying cycle. Besides, the variation process of the physical and mechanical parameters, including mass loss, density, ultrasonic velocity, compression strength, peak strain, elasticity modulus, and secant modulus, can be divided into two stages: 0∼6th wetting-drying cycle, gently changing, and 6th∼12th wetting-drying cycle, drastically changing. The whole change process of these physical and mechanical parameters with the increase in the wetting-drying cycle number can be expressed with the exponential function in general. [ABSTRACT FROM AUTHOR]

Background: Pain is common in men undergoing rigid cystoscopy. Even with the application of a lubricant containing 2 % lidocaine, about 76 % of men suffer from mild to severe pain when undergoing rigid cystoscopy. The most painful part of the procedure for men is when the cystoscope passes through the membranous urethra. Song et al. (Neurourol Urodyn 29:592-5, 2010) did autopsies on males and found that the dorsal nerve of the penis (DNP), the terminal branch of the pudendal nerve, innervates the membranous urethra in 53.3 % of specimens. In addition, the urethral mucosa has branches of innervated DNP. Dorsal penile nerve block (DPNB) is usually used for circumcision in children, and it has been shown to provide effective analgesia for penile surgeries. In this study, we hypothesized that DPNB could reduce the overall pain level in men during rigid cystoscopy.Methods/design: The trial is a prospective, randomized, double-blind, placebo-controlled, single-center trial to evaluate the effectiveness and safety of DPNB in analgesia for men undergoing rigid cystoscopy. Participants will be enrolled and randomly allocated into one of three groups according to the different analgesia regimens: 1) tetracaine gel group (DPNB with saline), 2) DPNB group (DPNB with ropivacaine plus plain lubricant), 3) combination group (DPNB with ropivacaine plus tetracaine gel). The primary outcome of this study is the visual analog scale (VAS, 0-10) for pain at cystoscopic inspection of the external sphincter. VAS scores evaluated at other time points serve as secondary outcomes. Vital signs are secondary outcomes that address the discomfort and pain during the procedure. Furthermore, the incidence of adverse events as secondary outcomes will also be recorded for evaluation of the safety of DPNB in rigid cystoscopy. Clinical assessments will be evaluated prior to DPNB, at administration of the lubricant gel, at cystoscopic inspection of the penile and bulbar urethra, external sphincter, prostate, and bladder, as well as at withdrawal of the cystoscope.Discussion: This research will determine the effectiveness and safety of DPNB in men undergoing rigid cystoscopy. The results of this trial may have important implications for exploring the role of DPNB in analgesia for cystoscopy in men.Trial Registration: ClinicalTrials.gov identifier NCT02502487 (6 Jul 2015). [ABSTRACT FROM AUTHOR]

Well Yuanba 103H, located in Bazhong structure of eastern Sichuan basin, is a demonstration ultra-deep horizontal well deployed by Sinopec South-Western Branch. Colloid stabilizers, filtration control agents and lubricants were evaluated and selected in labs, and a type of polymer drilling fluid is developed. Throughout the fifth interval of horizontal section drilling in Well Yuanba 103H, the drilling fluid kept working smooth, owing to: 1) appropriate density lowered the risk of pipe-sticking; 2) MBT between 2% and 2.5% guaranteed the high temperature stability; 3) synergy of efficient lubricants rendered the mud with good lubricity; 4) weak turbulent flow pattern kept the hole clean in annular space with large size and low flow rate. Application results showed that, this polymer drilling fluid system has good temperature resistance, contamination tolerance and lubricant effects. [ABSTRACT FROM AUTHOR]

With the development of the economy and manufacturing industry, tribology research in China has experienced a fast growth over recent decades. This review gives an outline for the research progresses achieved by Chinese scientists and engineers in various subjects, including elastohydrodynamic lubrication (EHL) and mixed lubrication, nano-tribology, lubricants and additives, tribo-materials and coatings, tribology issues in biology and bionics, wear of materials, and tribological design that transfers research achievements to the design process of machine components. In comparison with the vastness of research activities and Chinese economy, this article is written by the present author, based on limited information and knowledge, but it may help tribologists around the world to get a better idea about what has been done by their counterparts in China, which would encourage communication and cooperation in tribology research. [ABSTRACT FROM AUTHOR]

To solve the problems of unsustainability and low biodegradability of mineral oil-based lubricants, an agro-waste to biolubricant supply chain was proposed. A plant wax was extracted from the non-medicinal part of Codonopsis pilosula , and its composition, thermal stability, and lubrication behaviours were investigated. The plant wax was composed mainly of the esters of fatty acids and triterpenes. The natural wax showed good thermal stability and lubricity over the wide temperature range of 25–150 °C and load range of 100–250 N. These intriguing properties indicate that this plant wax can be used as a sustainable biolubricant in an open system or in food processing industry. This work simultaneously provides a strategy to realise the utilisation of the abundant non-medicinal parts of medicinal herbs abandoned in China. The agro-waste to biolubricant supply chain conforms to the goal of cleaner production and technical processes. Image 1060 • Natural wax from the non-medicinal part of Codonopsis pilosula has good lubricity. • Natural wax displays good load-carrying capacity and thermal stability. • The lubrication mechanism of the wax is boundary lubrication. • This work provides a new sustainable feedstock for green bio-lubricant. • It provides new strategy to eliminate waste in medicinal plant production in China. [ABSTRACT FROM AUTHOR]

Shell is to build a new, state-of-the-art lubricants blending plant in Nangang, Tianjin, Beijing, China. [ABSTRACT FROM AUTHOR]

Shell (China) Ltd is planning to build a world-scale lubricants blending plant in South China to meet growing demand in the region. [Copyright &y& Elsevier]

The article reports that BP is constructing an industrial lubricants blending facility with an initial investment of 22 million dollars in China. The new plant is expected to have an initial production capacity of 45 million liters and will bring a complete line of industrial lubricants and metalworking fluids. The industrial facility is planned to have a computerized automated batch blender configuration that can make it produce over 400 products from 500 different types of raw materials.