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Studies on the iodine-sulfur (IS) thermochemical cycle for hydrogen production has been carried out since about 2005 by the Institute of Nuclear and New Energy Technology, Tsinghua University, China. The HI decomposition occupies the important position of hydrogen generation in the IS cycle. In this paper, the HI-100 test apparatus with a H 2 production rate of 100 L/h was constructed and the HI decomposition was tested. First, the process and components for HI decomposition were designed. Then, the key components, including the feed tank, evaporator, gas heater, adiabatic reactor, condenser, and gas-liquid separator were made of industrial materials. After building this apparatus, the sealing test, heating water test, and HI decomposition have been conducted. The stable hydrogen production operation of more than 100 L/h had been achieved for 5 h, the maximum hydrogen production reached approximately 130 L/h, and the hydroiodic acid decomposition rate maintained about 22 %. The test results provide the design and experimental guidance for further amplification of HI decomposition for hydrogen production by the IS cycle. • The HI-100 test apparatus with the H 2 production rate of 100 NL/h was constructed. • An HI decomposition test for iodine-sulfur hydrogen production cycle was carried out. • The stable hydrogen production operation of above 100 L/h was achieved for 5 h. • The maximum hydrogen production rate reached about 130 L/h in HI-100 apparatus. • The hydroiodic acid decomposition rate maintained about 22 %. [ABSTRACT FROM AUTHOR]

In order to reduce the labor intensity and improve the efficiency of pruning, this study designed a multi-section luffing apple pruning equipment suitable for apple orchards in hilly and mountainous areas of China. In the essay, the structure and working principle of the equipment are expounded, the cutter was analyzed, and the parameters were determined. Using the self-made test bench to simulate the field experiment, this study selected the ratio of cutting speed to feeding speed and feeding speed as the influencing factors and took the cut-off rate, cutting efficiency and cutting power as the objectives to carry out single factor experiment and quadratic regression orthogonal experiment. The test results show that the cutting power increases with the increase of ratio of cutting speed to feeding speed, and the cut-off rate and cutting efficiency first increase and then decrease. As the feeding speed increases, the cutting efficiency and power increase, and the cut-off rate decreases. When the cutoff rate was greater than 80%, the optimal combination of operating parameters was the feeding speed of 0.55 m/s and ratio of cutting speed to feeding speed of 1.29. Under this combination, the cut-off rate was 84.9%, the cutting efficiency was 13.1, and the cutting power was 175.7 W. The error between the predicted target value of the model and the average measured target value was less than 7%, so the test results are reliable. According to the obtained optimal operating parameters, the actual cutting experiment of the pruning equipment in the field was carried out, and the cutting rate was 96.3%, which meet the design requirements. This study can also meet the needs of mechanized pruning of fruit trees with different crown shapes, improve the applicability of pruning equipment, and provide support for the development of mechanized pruning equipment in China. [ABSTRACT FROM AUTHOR]

In view of the limitations of several existing stress measurement methods under extremely high stress conditions (stress − strength ratio σ / R c > 0.5), this paper proposes a slot relief method based on partial deformation recovery to measure rock mass surface stress under extremely high stress conditions and justifies its viability with the help of an infinite element model. This method is then used to measure and study a research tunnel in West China's Jinping II Hydropower Station, where the maximum stress measured reached 80 MPa. In the process of measurement, this method needs neither complete borehole core nor ultrahigh pressure equipment. On the contrary, the test equipment is easy to carry and operate on, suitable for rock mass surface stress measurement under extremely high stress conditions, and able to provide in situ stress measurements for cavern rockburst prevention and slope management. [ABSTRACT FROM AUTHOR]

The study aimed to explore the potential effect of short-term visual perceptual training based on virtual reality (VR) and augmented reality (AR) platforms in postoperative strabismic patients. We enrolled 236 postoperative strabismic patients, among whom 111 patients received VR-based training, and 125 patients received AR-based training. The stereoacuity of 1.5 m and dynamic stereopsis were improved by VR training; meanwhile, AR training exhibited more improvement in stereoacuity of 0.8 and 1.5 m, dynamic and coarse stereopsis. It was suggested that the visual perceptual training based on VR and AR technology can be potentially applied in postoperative strabismus treatment to promote the recovery of binocular vision. [ABSTRACT FROM AUTHOR]

Dynamic compaction is a cost-effective foundation treatment technology, that is widely used in various types and conditions of foundations. However, due to the limitation of natural conditions (water content between 3% and 8%) in north-western China, it is difficult to meet the requirements of the optimal water content during dynamic compaction. To better treat a foundation with a low water content, a series of model tests were carried out by using homemade test equipment to study the influence of the ramming energy and η value on the efficiency of dynamic compaction under a low water content. The results showed that the improvement of the energy level could compensate for the poor effect of dynamic compaction caused by a low water content in arid regions. Compared with that at the optimal water content, the efficiency of dynamic compaction was 58.1% to 66.2% at a low water content and excited the optimal energy level. Increasing the η value was also beneficial to improving the effect of dynamic compaction. Hence, the optimal energy level combined with the appropriate η value is of great merit in treating the foundation of arid regions by using the dynamic compaction method, which provides new parameter suggestions and engineering guidance for dynamic compaction construction in arid areas. [ABSTRACT FROM AUTHOR]

PM 2.5 separator directly affects the accuracy of PM 2.5 sampling. The specification testing and evaluation for PM 2.5 separator is particularly important, especially under China's wide variation of terrain and climate. In this study, first a static test apparatus based on polydisperse aerosol was established and calibrated to evaluate the performance of the PM 2.5 separators. A uniform mixing chamber was developed to make particles mix completely. The aerosol concentration relative standard deviations of three test points at the same horizontal chamber position were less than 0.57%, and the particle size distribution obeyed logarithmic normal distribution with an R 2 of 0.996. The flow rate deviation between the measurement and the set point flow rate agreed to within ± 1.0% in the range of − 40 to 50°C. Secondly, the separation, flow and loading characteristics of three cyclone separators (VSCC-A, SCC-A and SCC112) were evaluated using this system. The results showed that the 50% cutoff sizes (D 50) of the three cyclones were 2.48, 2.47 and 2.44 μm when worked at the manufacturer's recommended flow rates, respectively. The geometric standard deviation (GSD) of the capture efficiency of VSCC-A was 1.23, showed a slightly sharper than SCC-A (GSD = 1.27), while the SCC112 did not meet the relevant indicator (GSD = 1.2 ± 0.1) with a GSD = 1.44. The flow rate and loading test had a great effect on D 50 , while the GSD remained almost the same as before. In addition, the maintenance frequency under different air pollution conditions of the cyclones was summarized according to the loading test. Unlabelled Image [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the first Internet-based collaborative pseudo-dynamic testing of a multi-span bridge system in mainland China is presented in detail, which has been carried out by the collaboration of Hunan University (HNU), Harbin Institute of Technology (HIT) and Tsinghua University (TU) in mainland China, and the University of Southern California (USC) in the USA. The prototype system of Russion River Bridge at Southern California in America is illustrated. Different testing specimens, testing equipments and substructure boundary conditions at HNU and HIT laboratories are described. A network protocol platform for collaborative pseudo-dynamic testing, called NetSLab, and some function modules developed on the use of its standardized interface are introduced. Aiming at the MTS system widely used in structural testing, two approaches are presented to implement the communication interface between NetSLab and testing equipment, respectively, studied by HNU and HIT. The integrated networked testing system and collaborative testing procedures are presented. The testing results manifest that the networked collaborative testing system with powerful capability provides a testing platform with good coordination for complex models or actual structures, and achieves remote sharing of testing equipments. [Copyright &y& Elsevier]

In recent years, under the advocacy of ITTC, large-scale model test technology has garnered significant attention from researchers all over the world. Increasingly sophisticated test equipment and a large amount of experimental experience have promoted the development and improvement of test technology. Here, a 25 m long bulk carrier model was built as the research object. The self-propulsion test about propulsion performance in real sea environment was conducted in the coastal waters of northern China. The manoeuvrability test proved that the designed ship model integrated system was reliable. The effects of complex wake field environments on the propulsion performance were studied using the equal thrust and equal torque methods. The results indicated that the complex wake field environment causes the torque to increase by 2%–11%, and the thrust loss ranges from 3 to 15%. When the propeller was operated at a high rotating speed, the torque and thrust in the oblique wave tended to decrease by 1–3% compared to the propulsion performance in the head wave. In addition, the more severe sea state caused the propeller torque to decrease and the thrust to increase. • A large-scale ship model with a length of 25m is built. • The self-propulsion test in real sea environment is carried out. • The self-propulsion instrument was developed to measure the thrust and torque generated by the propeller. • The influence of complex field environment on propeller performance is studied. [ABSTRACT FROM AUTHOR]

The article presents a comment on non-destructive testing (NDT) in China by the Technical Committee, The British Institute of Non-Destructive Testing. The Committee reports that NDT industry in China is still growing, so it is important. There is also increased recognition in China that quality control and health and safety are paramount. Both of these issues have driven the demand for NDT - practice and research.