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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]

Coal seam pre-drainage technology is widely used to prevent and control gas in China's high-gas coal seams, and upward drilling is a safe and reliable technology. Using the Luling Coal Mine as the study location, according to the actual situation of the site, a layer-through drilling process was proposed. Relying on a cross-layer extraction borehole, coal seam water injection efficiency extraction and high-efficiency water injection dust prevention can be performed in the later stage of borehole extraction, enabling one-hole multi-purpose and "gas-powder" integrated prevention and control. In order to study the "stress-seepage" coupling characteristics of the coal around the borehole, a numerical simulation of the coal seam water injection process was conducted. Based on the simulation results, a field test of water injection in coal seam upward drilling was performed. The field monitoring data show that the water injection and water content of the coal seam were increased by about 3.07 m3 and 0.69%, respectively, compared with the traditional water injection process. The water injection effect is remarkable, which is of great significance to ensure the safe and efficient production of the mine. [ABSTRACT FROM AUTHOR]

Based on the hidden karst exposed in Jurong Pumped Storage Power Station, combined with the field exploration data, the temporal and spatial development characteristics of hidden karst in the power station area are analyzed using the methods of specific solubility and specific corrosion, water chemical composition analysis, borehole television imaging, tracer test, and water pressure test. The results show that the karst development in the study area can be divided into three periods: pre-Cretaceous, Pleistocene, and modern karst. Karst development is controlled by soluble rock, non-soluble rock, and their combination, and the development direction is basically consistent with the fault strike. Karst caves are mainly distributed below the elevation of 100 m, with different shapes and scales and randomness. Non-soluble rocks and impure carbonate rocks are widely distributed in the study area, and surface karst is not developed. The underground karst caves are filled with red clay, and the rate of groundwater circulation is slow. The existence of geological bodies such as rock veins causes the groundwater levels to have obvious double-layer characteristics, which results in weak connectivity between karst caves. Although the karst in the power station area has a certain hydraulic connection with the surface water outside the area, the hydraulic connection of karst in the power station area is generally weak. The research results provide a scientific basis for the anti-seepage measures of underground powerhouses. [ABSTRACT FROM AUTHOR]

Clay-based barrier wall has been diffusely employed as vertical barriers. Nevertheless, there were few project practices of these walls in China. And few research have been performed to study the impact on the permeability of the addition of domestic bentonites. To solve this problem, the influences of bentonite level on hydraulic conductivity, porosity and clay-bound water of soil-bentonite admixtures have been assessed employing a flexible-wall test and water centrifugal dewatering experiment with various bentonites. The outcomes revealed that as barrier walls are constructed by blending bentonite and Fujian standard sandy soil, there is a critical bentonite level of the smallest porosity. If the bentonite level is less than the critical bentonite content, hydraulic conductivity is reduced quickly, while if the bentonite level is greater than the critical bentonite content, hydraulic conductivity is reduced gently. Additionally, as the bentonite level grew, the clay-bound water centage of the admixtures continually improved. Supposing that the clay-bound water enclosed the clay grains, a near computation approach of the effective porosity is put forward and showed that the effective porosity decreased with bentonite content. Additionally, an exponential relationship was found between the effective porosity and the permeability. [ABSTRACT FROM AUTHOR]

External water (such as rainwater, mountain water and groundwater) will decrease the inflow contaminant concentration in urban sewage plants, and pose challenges in improving the wastewater treatment quality and efficiency. Therefore, removing the external water is vital for this target. A sewage plant in Zhuhai, China, was considered as an example. By performing online flow monitoring, water quality testing, on-site survey and data analysis, the rainfall-derived inflow and infiltration of the sewage system were quantitatively analysed through the pollutant balance method. By proposing key emphases of severe problems, the presented findings will aid in sewage system maintenance and pipeline network renovation. [ABSTRACT FROM AUTHOR]

Based on the water quality test data of 257 groups of phreatic groundwater and 165 groups of confined groundwater in the Nanchang area and the redox conditions, acid–base conditions and the organic matter content in groundwater, we identified hydrochemical characteristics and genesis of groundwater with high Fe and Mn contents in Nanchang. The results showed that Fe and Mn exceeded the standard in both phreatic and confined groundwater. The over-standard rates of Fe and Mn in groundwater were 8.56–11.52% and 33.07–36.36%, respectively. The degree of pollution Fe and Mn in the confined groundwater is higher than that in the phreatic groundwater, and the degree of pollution caused by Mn is higher than that caused by Fe. The high Fe and Mn contents in groundwater were caused by the release of Fe and Mn minerals from the native environment due to changes in the groundwater environment of the study area. A mild redox environment (Eh < 100) and low pH value are favorable for Fe and Mn enrichment in groundwater. The presence of organic matter accelerates microbial activity and promotes the release of Fe and Mn from aquifer sediments. Therefore, the change in the native environment played an important role in the increase in Fe and Mn content in the study area. [ABSTRACT FROM AUTHOR]

In western China coal mines, the mining-induced caving zone is regarded as a main pathway for water and sand inrush mixture hazards. The paper experimentally studied the flow behavior and the mechanism of water and sand mixture through mining-induced caving zones. Transport experiments are performed by using a laboratory-scale model, and the caving zone is modelled by using different sizes of glass beads. Four different sand sizes are used for the sand layer. The test results reveal that the mass flow rate of sand and water mixture increases with the increase of the initial water head. And an equation is proposed for the mass flow rate of sand and water mixtures that correctly reproduces the data for all the conditions. In addition, the sudden decreases in water head loss is monitored at the commencement of the water and sand flow, which would result in a large number of sand particles that rapidly start up and make the kinetic energy transfer from water to sand. [ABSTRACT FROM AUTHOR]

Purpose: The paper aims to investigate the new market entry strategy of the international grocery retailers Aldi Süd and Costco in China; analyzing if and how their prior-online market entry reflects a strategic response to organizational challenges in the Chinese market, which is a pioneer in the use of digital technologies and the provision of digital services. Design/methodology/approach: The article identifies major challenges faced by international grocery retailers in China and discusses these with the help of the conceptual approach of embeddedness. The paper is based on expert interviews with senior executives of the two international retailers and other retail specialists and consultants. Findings: The prior-online market entry by Aldi Süd and Costco represents a strategic response to organizational challenges that have to be faced in an increasingly challenging and highly digitalized Chinese market. Prior-online market entry allows the two retailers to experiment with the unique and heterogeneous Chinese market and build network and territorial embeddedness to facilitate the establishment of the physical store network. Both retailers utilize online stores to build relation and network with suppliers and customers and to understand Chinese consumer preferences. Yet, the localization strategy of Aldi Süd and Costco vary greatly. Originality/value: Grocery retailers' prior-online expansion strategy has not yet been the focus of academic research. In regard to global grocery retailers, such as Aldi Süd and Costco, previous research argued that they were prepared to accept a lower expansion speed in order to expand at minimum risk and cost and mainly in countries which are regarded as having higher cultural proximity. The paper reveals the potential of the prior-online market entry strategy to change the internationalization behavior of grocery retailers. In addition, it contributes to the understanding of the evolution of market entry strategy into advanced digital economies in the coming new decade. [ABSTRACT FROM AUTHOR]

Variation of pore water pressure in soil grains, caused by the force of waves repeatedly acting on the seabed, is the main reason for soil liquefaction. In the study of wave-induced pore pressure response, field monitoring is closer to the real situation than other research methods. In this study, pore pressure in the easily liquefied zone of the Yellow River Estuary was measured in a long-term, high-precision way using self-designed pore pressure observation equipment. Both total and excess pore pressure were analyzed by comparison with the hydrodynamic conditions. Results showed that the total pore pressure was influenced by waves and tides, whereas excess pore pressure was influenced only by waves. Transient liquefaction occurred at a seabed depth of 0.5 meters (m), but no residual liquefaction occurred during the observation period. The maximum depth at which waves influenced pore pressure was between 0.5 and 1.5 m. The factors influencing pore pressure and the reason there was no residual liquefaction are discussed. The effects of pore water pressure response are mainly determined by the relationship between hydrodynamic action and the soil's liquefaction resistance. By comparing normalized in situ observation data and water flume test data, we found that the effect of waves on pore water pressure under actual marine conditions is much smaller than that in water flume tests with equal scale reduction. To better represent the wave-induced pore pressure response results, the relationships between pore pressure increments induced by waves and decrements due to seepage are summarized in a graph and divided into three categories: no response, oscillatory without accumulation, and affective accumulation. [ABSTRACT FROM AUTHOR]

According to the current status of no design technology for large-scale horizontal LPG mounded pressure storage tank at home, the design and simulation analysis of the first type in China is carried out according to ASME VIII Div1&2 and EEMUA190 standards. The results show that when the tank body is inflated, there is a great stress on the joint between the head and the tank wall, and will be obvious on the surface when the tank body is settled in the middle; from the comparison of seismic conditions and normal operating conditions, the earthquake has a greater impact on tank settlement while a little stress on the tank body; under normal operating conditions and water pressure test, the tank material don't reach the material yield point, and there are some margins, so the tank body design is reasonable and can be adapted to work under various working conditions. [ABSTRACT FROM AUTHOR]

When building a multi-parameter water quality testing model for marine environmental pollution emergency response, the characteristics of marine environmental data are analyzed based on the method of a data-driven model artificial neural network, and the mapping relationship between state variables of the marine environment is established by taking state variables of the marine environment as input-output parameters of the model. The method of emergency multi-parameter inversion of the combined unit model is used to optimize the inversion of emergency parameters (chemistry and biology) of a data-driven model with regional variation, and to invert the near-optimal solution. Based on the inversion results, a non-conservative water quality testing model of marine environmental pollution is constructed from the two emergency parameters of chemistry and biology. This model mainly studies the decomposition rate of nitrogen and phosphorus and the effects of phytoplankton growth, respiration, withering and sedimentation on the nutrient value from the two aspects of chemical decomposition speed and biological process which affect the change of the nutrient value of marine environmental pollution. The water quality concentration of the marine environment is determined according to nutrient value, and the ocean ring is realized. The test results of the water quality test model are as follows: the predicted values of chlorophyll and inorganic nitrogen content in Liaodong Bay and Bohai Bay, China is in good agreement with the measured values, and the predicted values of inorganic nitrogen, chlorophyll current and water level in the nutrient salts of Liaodong Bay and Bohai Bay are in good agreement with the measured values. The test results are of high accuracy. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate whether the finger skin temperature (FST) after cold provocation (10 °C, 10 min) is as a useful indicator for assisting in the diagnosis of vibration-induced white finger (VWF) in a group of polishers in a subtropical environment. Method: Ninety male vibration-exposed metal polishers (30 patients and 60 controls) from the Guangdong Province in Southern China were recruited. The FSTs at 30, 20, 10, and 0 min before cold water immersion (FSTpre-30, FSTpre-20, FSTpre-10, and FSTbaseline) and 0, 5, 10, 15, 20, 25, and 30 min after immersion (FST0, FST5, FST10, FST15, FST20, FST25, and FST30) were measured on the index, middle, and ring fingers of both hands. Results: During the first 20-min adaptation period, there was a significant increase in FST in three fingers on both hands in the two groups. In contrast, there were no significant differences between FSTpre-10 and FSTbaseline. Furthermore, FSTpre-30, FSTpre-20, FSTpre-10, and FSTbaseline of the three fingers in both hands did not differ significantly. During recovery, the indicators FST5–0, FST10–0, R5, and R10 for the index finger of the left hand in patients were lower than for the controls. Among the various indicators, the absolute recovery rate, FST5–0, at 5 min after immersion was identified as the best diagnosis indicator with a sensitivity of 76.7% and specificity of 70.0% when applied to the index finger of the left hand. Conclusion: The cold water immersion test as applied in a subtropical environment can have a fair discriminating ability for diagnosing VWF. [ABSTRACT FROM AUTHOR]

The chemical characteristics of Ordovician formation water and its relationship with hydrocarbons in the Halahatang depression (Tabei Uplift, Tarim Basin, NW China) were analyzed on the basis of the detailed formation water test data. The formation water in the Halahatang depression can be characterized as CaCl2 type with high total dissolved solids (TDS) generally. The TDS concentration has a weak negative relationship with the depth, and is above 200 g/L in the North Region (north of the pinch-out line), then gradually decreases to the south, but is still greater than 50 g/L. The ion-proportionality coefficients of formation water, including the sodium-chlorine coefficient, desulfurization coefficient and metamorphic coefficient, reflect that the present strata are well sealed and had once experienced strong water-rock interactions. Furthermore, the source and evolution of the formation water presents a closed relationship with the hydrocarbon accumulation. The meteoric source of the formation water indicates the denuding by the Ordovician formation and the damage from the previous oil and gas reservoirs. The reservoir quality was also improved due to the strong karstification during the denudation, which was beneficial for hydrocarbon accumulation. The distribution of the TDS concentration is controlled by the caprock (Sangtamu Formation) and the high salinity fluids from overlying strata and adjacent regions. A geological model was established, the high salinity fluids penetrated the Ordovician strata resulting in the TDS increases in the northern part. Whereas, the South Region (south of the pinch-out line) was less affected due to the shielding layer of the O3s. The favorable preservation conditions reflected by the high TDS and ion-proportionality coefficients correspond to the stable subsidence of strata since the Triassic era, the oil and gas reservoirs formed in the Himalayan can be preserved. [ABSTRACT FROM AUTHOR]

Loess collapse is an important factor in earth fissure formation, and earth fissures resulting from loess collapse are widely distributed in loess areas in China. To explore the basic features and formation mechanism of collapsible earth fissures, we conducted an in situ water immersion test in a loess area. This paper describes the genesis of collapsible earth fissures by monitoring the development processes of collapsible settlement and earth fissure formation. This paper demonstrates that the infiltration process can be divided into three stages, and the subsidence curve of the whole test process can be divided into six stages. During the test, the collapsible deformation gradually developed outward, the collapsible settlement decreased with increasing distance from the test pit, and the horizontal influence distance was approximately 18 m. The collapsible earth fissures were parallel to the test pit, and characterised by horizontal tension and vertical dislocation. With the collapsible deformation expanding outwards, the location of the earth fissure developed outwards. The tensile stress and tensile strain caused by the differential collapsible deformation caused the formation of collapsible earth fissures. When the tensile strain or tensile stress was greater than the ultimate tensile strain or tensile strength, the loess experienced tensile failure and formed an earth fissure. • Collapsible subsidence section showed symmetry, forming a "U" shape. • Collapsible earth fissures are characterized by horizontal tension and vertical dislocation. • Tensile stress and tensile strain are main factors for collapsible earth fissures formation. [ABSTRACT FROM AUTHOR]

Water hazards threat the safety of underground mining. A detailed characterization of hydraulic parameters is helpful for the design of engineering projects to prevent underground water hazards. Utilizing aquifer's natural artesian condition, water releasing tests are often performed in China's underground mines. In this research, we propose to interpret water releasing test data with hydraulic tomography (HT) technique. A 216-hour duration test was performed to localize water hazard areas in Ningtiaota underground coal mine. Groundwater was released with four sequential stages from 30 boreholes. HT analysis clearly shows that the study area has a potential water hazard region in southern part by only using data from the first two stages, which coincides with existing water inrush incident location. With the addition of more pressure responses from stages 3 and 4, it discovers low transmissivity and storativity values in northern part. Our numerical examples further demonstrate that sequential water releasing tests produce comparable hydraulic parameter distributions to tomographic tests. In the end, we conclude that water releasing tests aided by HT technique can leads to a high resolution characterization of water hazard aquifers. [ABSTRACT FROM AUTHOR]