An analysis of China’s investment in the hydropower sector in the Greater Mekong Sub-Region

The Mekong River’s natural resources offer large benefits to its populations, but it also attracts the interest of foreign investors. Recently, Chinese firms, banks and government bodies have increasingly invested in large hydropower projects in the Greater Mekong Sub-Region. Due to China’s rapid economic growth, its rapid industrialisation and its limited domestic natural resources, the Chinese government has issued the ‘Going Out Strategy’ which promotes investments in overseas natural resources like water and energy resources. In search for climate-friendly low-carbon energy, cheap electricity and access to a growing market, Chinese institutions turn to Southeast Asia where Chinese institutions are currently involved in more than 50 on-going large hydropower projects as contractors, investors, regulators and financiers. These Chinese institutions have influence on environmental and social practices as well as on diplomatic and trade relations in the host countries. Currently, there are major gaps in understanding who is engaged, why, how and with what impacts. This paper therefore aims to assess the motives, actors, beneficiaries and the direct and indirect impacts of China’s investment in large hydropower projects in the Greater Mekong Sub-Region. The authors use the ‘Rising Powers Framework’ to assess these issues, which is an adapted version of the Asian Drivers Framework.     

The recovery of the lower montane cloud forest in the Mucujún watershed, Mérida, Venezuela

High deforestation rates in tropical countries continue to reduce forest cover and thereby habitat quantity and quality. However, in some places the forest is recovering and expanding thus offsetting the biodiversity and ecosystem service losses. In order to characterize the forest recovery, land use and land cover (LUC) changes were analyzed using aerial photographs, taken between 1952 and 2009, of a peri-urban watershed in the Andes region of Venezuela. The qualities of the changes were assessed using landscape indices and hemeroby indicators. In that period, the forest cover increased about 18 %, mainly due to abandoned pastures on steep slopes. At the same time, the urban area expanded about 4 % on valley bottoms, while pastures and crop fields were reduced about 20 %. The results also showed that forest patches were aggregating, whereas pastures were fragmenting. A reduction in direct human impacts on forests growing on abandoned pastures resulted in a slight recovery of the lower montane cloud forest structure and plant composition. But non-native species were found in all LUC categories. During the study period, we documented not only forest recovery, but also urban area growth, intensified land use and invasions by non-native species all of which could partially counterbalance the positives of forest recovery.     

A Device for Preventing Occupational Diseases of Lower Legs

Physiological processes characteristic of the fatigue of legs mainly appear when the worker’s activity requires standing. If the processes are intensive and regular, various diseases of legs, such as varicose veins and musculoskeletal disorders of legs and feet, can develop. Therefore, methods of reducing the fatigue of legs are important in occupational health protection. Air jet massage technology was developed and an appropriate massage device was built by the authors. The massage head turning around the lower leg and moving up and down gradually covers the leg’s surface. To determine the efficiency of the massage, fatigue processes were studied. These studies showed that jet massage effectively reduces both the subjective and objective fatigue symptoms. The device is convenient for use in industry, services, and at home.     

Prediction of Duration Limited Exposure for Participants Wearing Chemical Protective Clothing in the Cold

The suitability of the IREQ (insulation required) index for predicting the thermal responses of 6 participants wearing chemical protective clothing was tested during exercise at -20 and -25 °C. IREQ was used to calculate duration limited exposure (DLE). Measured DLE correlated (r= .899, p < .001) with the predicted DLE. In exposures exceeding 40 min, however, the predicted DLE tended to be 10-20 min too short compared to the measured one. During short exposures the prediction was 5-20 min too long. The results show that IREQ overestimated the cold strain in participants wearing chemical protective clothing during cold exposures longer than 40 min. Nevertheless, predicted DLE never exceeded measured times and thus the prediction was always safe from the occupational point of view.     

Psychosocial and Ergonomic Factors,and Their Relation to Musculoskeletal Complaints in the Swedish Workforce

A random sample of 1 000 subjects (20–65 years old) from the national population of Sweden received a questionnaire; 70% (n = 695) replied, of whom 532 were occupationally active. Female gender, working with neck and/or body bent forward, arms above shoulders, and precision work tasks were predictors of musculoskeletal symptoms. Neck, shoulder, and upper back symptoms were more common in a strained situation at work (high demands, low control) (adjusted odds ratios [adjOR] 2.76, 2.80, and 2.26, respectively). Among females, neck and shoulder symptoms were more common in an iso-strain situation (high demands, low control and low social support) (adjOR 4.43 and 3.69, respectively), and low back symptoms were more common at low social support combined with a passive work situation (adjOR 3.35). No associations were found between iso-strain model and symptoms among males. In conclusion, iso-strain work situation was associated with neck symptoms among females, even when controlling for ergonomic factors.     

Subjective Annoyance Response to Diesel Engine Sound During Idling Conditions

Subjective annoyance response to diesel engine sound during idling conditions was evaluated by 80 participants. Eight different sound spectra were presented to the participants at a constant level of 80 dB(A) in a paired comparison procedure. Stereo-recorded sound stimuli were played back through a pair of loudspeakers in an anechoic room. Four objective parameters of loudness, sharpness, impulsiveness, and roughness were found to be the determining factors that cause subjective annoyance. An annoyance prediction model for the test stimuli of an idling diesel engine was developed on the basis of these factors. The objective parameters and their interactions have a significant effect on the annoyance prediction model. The spectral distribution indicated by test participants to be pleasant can be used as a basis for appropriate modification of engine sound. A single microphone measurement in free field conditions can be used to estimate objective parameters for defining the cause of annoyance.     

Thermal Strain in Fire Fighters While Wearing Task-Fitted Versus EN 469:2005 Protective Clothing During a Prolonged Rescue Drill

Fire fighters are normally overprotected during their working hours because of the tendency to keep the personal protection level sufficiently high in case of the worst possible scenarios. This study investigated the effects of task-fitted protective clothing on thermal strain in fire fighters as compared to EN 469:2005 protective clothing during a prolonged (2 1/2 hrs) job-related rescue drill under neutral and hot climates. The subjects were 23 healthy, physically fit professional male fire fighters aged 26–44 years. Measurements included cardiovascular and thermal responses and subjective assessments. Wearing task-fitted clothing during rescue tasks in a neutral climate considerably reduced total thermal and cardiovascular strain in prolonged rescue work. The fire fighters also perceived physical work as significantly harder on average, and reported more intense subjective discomfort while wearing EN 469:2005 as compared to task-fitted clothing.     

A large-scale experiment on mass transfer of trichloroethylene from the unsaturated zone of a sandy aquifer to its interfaces

A large-scale experiment was conducted to investigate the transport of trichloroethylene (TCE) vapors in the unsaturated zone and to determine the mass transfer to the groundwater and the atmosphere. The experiment involved injection of 5 1 of TCE in the unsaturated zone under controlled conditions, with multidepth sampling of gas and water through the unsaturated zone and across the capillary zone into underlying groundwater. The mass transfer of TCE vapors from the vadose zone to the atmosphere was quantified using a vertical flux chamber. A special soil water sampler was used to monitor transport across the capillary fringe. Experimental data indicated that TCE in the unsaturated zone was mainly transported to the atmosphere and this exchange reduced significantly the potential for groundwater pollution. The maximum measured TCE flux to the atmosphere was about 3 g/m(2)/day. Observed and calculated fluxes based on vertical TCE vapor concentration gradients and Fick's law were in good agreement. This confirms that TCE vapor transport under the experimental conditions was governed essentially by molecular diffusion. TCE vapors also caused a lower, but significant contamination of the underlying groundwater by dispersion across the capillary fringe with a corresponding maximum flux of about 0.1 g/m(2)/day. This mass transfer to groundwater is partly uncertain due to an inadvertent entry of some nonaqueous phase liquid (NAPL) from the source area into the saturated zone. Application of an analytical solution to estimate the TCE flux from the unsaturated zone to the groundwater indicated that this phenomenon is not only influenced by molecular diffusion but also by vertical dispersion. The mass balance indicates that, under the given experimental conditions (e.g. proximity of the source emplacement relative to the soil surface, relatively high permeable porous medium), nearly 95% of the initial TCE mass was transferred to the atmosphere.     

Adsorption of PCDD/F on MWI fly ash

The removal of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F) from waste incinerator off-gas is a costly task, because a considerable part of the PCDD/F may exist in the gas phase (often 50-100% around 200 degrees C). The volatile fraction passes the particle filter and the subsequent gas cleaning equipment, so that an additional unit is needed to remove the gaseous PCDD/F from the flue gas. Moreover, dioxins and furans can accumulate in some parts of the equipment in a way that they can act as a latent source. In this work, we investigate the possibility to adsorb the PCDD/F at the fly ash particles and to remove them during the filtration. The gas/particle partitioning of the PCDD/F depends on the temperature, the vapor pressure, the particle size, the particle number density and on the physical and chemical properties of the particle surface. These relationships are investigated by model calculations and by pilot scale experiments (500 Nm3/h) which employ one selected hexachlorinated dioxin congener. At room temperature, approx. 90% of the HxCDD are found in the particulate phase, while at 135 degrees C that portion is only 10%. This means that at ambient temperatures, the gas/particle partitioning of the dioxin corresponds well to the sublimation equilibrium. At higher temperatures, it is much different from the sublimation equilibrium and the apparent adsorption enthalpy is smaller than the enthalpy of sublimation. This observation is in agreement with literature data. From the above experiments and from similar literature data, the efficiency of fly ash particles as a sink for PCDD/F can be evaluated. The data suggest that the adsorption rate is not the limiting factor for the transfer into the particulate phase. The important factors appear to be the chemical composition of the fly ash and the temperature.     

Attempt to model laboratory-scale diffusion and retardation data

Different approaches for measuring the interaction between radionuclides and rock matrix are needed to test the compatibility of experimental retardation parameters and transport models used in assessing the safety of the underground repositories for the spent nuclear fuel. In this work, the retardation of sodium, calcium and strontium was studied on mica gneiss, unaltered, moderately altered and strongly altered tonalite using dynamic fracture column method. In-diffusion of calcium into rock cubes was determined to predict retardation in columns. In-diffusion of calcium into moderately and strongly altered tonalite was interpreted using a numerical code FTRANS. The code was able to interprete in-diffusion of weakly sorbing calcium into the saturated porous matrix. Elution curves of calcium for the moderately and strongly altered tonalite fracture columns were explained adequately using FTRANS code and parameters obtained from in-diffusion calculations. In this paper, mass distribution ratio values of sodium, calcium and strontium for intact rock are compared to values, previously obtained for crushed rock from batch and crushed rock column experiments. Kd values obtained from fracture column experiments were one order of magnitude lower than Kd values from batch experiments.