Study on the mechanism of hydrate adhesion on the surface of rocks and minerals

Natural gas hydrate is mainly enriched in the low temperature and high pressure environment such as the extremely cold permafrost zone and the polar continental shelf, which is a renewable energy with great development value. The analysis of the adhesion mechanical properties of gas hydrate on the surface of rock and mineral is of great significance for the correct evaluation and effective control of the influence of gas hydrate on sedimentary layers. In this paper, an experimental device for visualizing the adhesion of hydrate wall under atmospheric pressure was built to directly test the adhesion strength of hydrate on the rock wall. The influence mechanism of the microstructure of rock wall and the types of rock minerals on the adhesion strength of hydrate was studied. It was found that the adhesion strength of hydrate on the sandstone wall was greater than that of carbonate rock salt. The higher the surface roughness of rock and mineral, the higher the adhesion strength of hydrate.

The influence of adolescents’ romantic relationship on individual development: Evidence from China

Based on China Education Panel Survey (CEPS) data, this paper explores the influence of adolescents’ romantic relationship on individual development in terms of academic, emotional, and interpersonal development. The research finds that the academic performance of adolescents who involved in romantic relationship is relatively lower and their risk of having negative emotions is also lower than their counterparts outside relationship. The romantic relationship provides an opportunity learning how to maintain intimacy relationship and build positive self-concept, and thus, it has a positive effect on growth of interpersonal ability. Due to differences in gender roles, the romantic relationship has a stronger impact on female adolescents. In addition, in a high-pressure environment, individuals with romantic relationship bear greater psychological pressures. A more open, tolerant, and supportive environment toward adolescents’ romantic relationship will promote their holistic development.

A stereoscopic PIV system for the Princeton Superpipe

Herein, we describe the design and testing of a stereoscopic PIV system uniquely adapted for the high pressure environment of the Princeton Superpipe. The Superpipe is a recirculating pipe facility that utilizes compressed air as the working fluid to attain very high Reynolds numbers. Commercial piping is used as the pressure vessel to hold pressure up to 220 bars, and a test pipe is enclosed inside with a development length of 200 diameters that ensures a fully-developed condition at the test section. The highest achievable Reynolds number (based on the bulk velocity and the pipe diameter) is 35×106, corresponding to a maximum friction Reynolds number of 5×105. The unprecedented range of Reynolds number has enabled a number of new insights in the behavior of high Reynolds number wall-bounded turbulence (Zagarola and Smits, 1998; Hultmark et al., 2013). However, past measurements in the Superpipe have been primarily restricted to single-component, one- or two-point statistics of fully-developed pipe flows. The present work aims to expand the capability of the Superpipe to study turbulent coherent structures and multi-point statistics by means of a new stereoscopic PIV system. The high pressure environment and the confined space inside the pressure vessel pose challenges to both imaging and seeding, the solutions to which will be discussed.

A study on the influence of family upbringing style on Teenagers' mental health

with the development of society, modern teenagers are in a high-pressure environment for a long time, which leads to some psychological problems, even suicide and other psychological problems. Each family's educational concept and educational environment are different. How to make teenagers have positive and healthy psychology has become a hot topic in the society. This article will discuss the influence of family upbringing on Teenagers' mental health.

Design and analysis of deepwater tension sensors for ice drill application

Monitoring the tension in cables is significant in some ice drill and deepwater applications. Take our RECoverable Autonomous Sonde (RECAS) for example. It is able to melt a hole to the bottom of ice sheet and is able to move upwards. A winch is installed inside RECAS to release and recover the cable, whose tension needs to be monitored in real time in order to control the behavior of the winch. The high pressure of deep water and limited installation space pose great challenges in sensor development. In this paper, two editions of newly designed deepwater tension sensors are proposed. The first edition is based on a fresh hydraulic load module that operates in high pressure environment and the second edition tension, which aims to improve the accuracy, applies a newly designed watertight load module. Detailed force transmission and characteristic analysis of the sensors are carried out. The sensors have got through a series of experiments, including calibration experiments, pressure experiments and field experiments. The resultant accuracy of the second edition sensor, which has a better performance, is over 2% under the measuring range of 1000 kg and the dimension of the final sensor is as compact as 150 mm × 137 mm × 86 mm.