UV-B辐射增强对不同大麦品种生理特性的影响

通过大田试验,研究了UV-B辐射增强对不同生育期3个大麦(Hordeum vulgare)品种光合和蒸腾生理特性的影响。试验设对照(自然光)和辐射增强(辐照强度14.4 kJ.m-2.d-1)2个UV-B辐射水平。结果表明,UV-B辐射增强明显抑制大麦光合作用和蒸腾作用。与对照相比,UV-B辐射增强可降低叶片叶绿素含量、气孔导度、净光合速率和蒸腾速率,但对胞间CO2摩尔分数基本没有影响。不同大麦品种对UV-B辐射增强响应的敏感性存在差异,单2号对UV-B辐射增强较为敏感,而苏啤4号较不敏感。     

Evaluation of Carbon Uptake and Emissions by Forests in Korea During the Last Thirty Years (1973–2002)

The contribution of Korean forests to carbon sequestration for anthropogenic carbon emissions was evaluated. In addition, monitoring of carbon species released from forest fires was conducted. Despite a high carbon uptake by Korean forests, a tremendous increase in fossil fuel burning resulted in a small contribution by forests to carbon removal. The removal efficiency had a 5–31% range with an average of 12% during the period 1973–2002. In 2000, the amount of carbon released from burned trees corresponded to 1.6% of carbon uptake by forests. The distribution of surface CO concentration (ppb) derived from MOPITT (Measurement of Pollution in the Troposphere) showed high CO levels over the East/Japan Sea on April 10, 2000 when the largest forest fires occurred along the east coast of Korea. Trajectory analysis and ground CO measurements also indicated that CO levels over the East/Japan Sea were influenced by forest fires. This study suggests that continuous monitoring of carbon emissions from forest fires is needed for a more reliable estimate of carbon flux in the environment.     

Joint Impact of Scaling and Hysteresis on NAPL Flow Simulation

The hysteresis of capillary pressure versus saturation (P–S) relation is an important constitutive relation in multiphase flow, since the P–S relation is widely used to predict P–S relations in the simulation of the non-aqueous phase liquids (NAPLs). This work examined the performance of the scaling rule on predicting the P–S relationship and then studied the joint impact of the scaling and hysteresis on the multiphase NAPL flow simulation. Various experimental P–S values of distinct fluid pairs were compared with the scaled P–S curves using the scaling rule. The comparison indicated that the prediction of P–S is more accurate when the water–air P–S curve is used to scale other P–S curves. The joint impact of the scaling and hysteresis on the NAPLs flow simulation was then investigated by numerical simulation studies. The NAPL simulator was used to simulate the outcome of several scenarios based on a system with water–NAPL–air in a hypothetical sand tank. For both gasoline and trichloroethylene, the difference of the injected NAPL volume between no hysteretic and hysteretic simulations over a given time period was the smallest when the water–air P–S curve was used to scale other P–S curves. Simulation results of this study are valuable references for predicting the distribution of NAPLs.     

Disinfection by-product formation and mutagenic assay caused by preozonation of groundwater containing bromide

Brominated organic and inorganic by-products are generated during ozonation of groundwater containing high bromide concentrations. This study measured concentrations of bromate, bromoform, bromoacetic acids, bromoacetonitriles, bromoacetone, 2,4-dibromophenol and aldehyde generated by ozonation. The potential mutagenicity of ozonated waters was assessed using the Ames and Microtox tests. Test results for the 18 ozonated groundwater samples demonstrate that bromate formation is associated with high pH, bromide and alkalinity content, low levels of dissolved organic carbon (DOC) and ammonia, and low alkalinity. Brominated organic by-products were correlated with high bromide ion and natural organic matter content, and low ammonia concentrations. The Ames test results demonstrate that all extracts from ozonated water have mutagenic activity; however, the 18 raw groundwater samples had no mutagenicity. The Microtox test results also show that the ozonated water samples were highly toxic. Generally, both bromide and DOC content promoted the formation of ozonation by-products and mutagenicity. Controlling of bromide and DOC concentrations is an effective method of reducing potential by-product formation and eliminating mutagenicity problems associated with groundwater ozonation.     

Co-pyrolysis of swine manure with agricultural plastic waste: Laboratory-scale study

Manure-derived biochar is the solid product resulting from pyrolysis of animal manures. It has considerable potential both to improve soil quality with high levels of nutrients and to reduce contaminants in water and soil. However, the combustible gas produced from manure pyrolysis generally does not provide enough energy to sustain the pyrolysis process. Supplementing this process may be achieved with spent agricultural plastic films; these feedstocks have large amounts of available energy. Plastic films are often used in soil fumigation. They are usually disposed in landfills, which is wasteful, expensive, and environmentally unsustainable. The objective of this work was to investigate both the energetics of co-pyrolyzing swine solids with spent plastic mulch films (SPM) and the characteristics of its gas, liquid, and solid byproducts. The heating value of the product gas from co-pyrolysis was found to be much higher than that of natural gas; furthermore, the gas had no detectable toxic fumigants. Energetically, sustaining pyrolysis of the swine solids through the energy of the product gas could be achieved by co-pyrolyzing dewatered swine solids (25% m/m) with just 10% SPM. If more than 10% SPM is used, the co-pyrolysis would generate surplus energy which could be used for power generation. Biochars produced from co-pyrolyzing SPM and swine solid were similar to swine solid alone based on the surface area and the ¹H NMR spectra. The results of this study demonstrated the potential of using pyrolysis technology to manage two prominent agricultural waste streams (SPM and swine solids) while producing value-added biochar and a power source that could be used for local farm operations.     

Optimal Design of a Multi-Pollutant Air Quality Monitoring Network in a Metropolitan Region Using Kaohsiung, Taiwan as an Example

An air quality monitoring network (AQMN) usually performs the basic function of assessment of regional air quality and demonstration of compliance with ambient air quality standards in an urban area. Different pollutants, however, may present different characteristic variabilities due to their specific emission patterns, rates of diffusion, and transport and transformation behaviors. But the costs of siting in a pollutant-specific monitoring network would be higher than that for a common network with respect to several pollutants monitored simultaneously. This paper presents a survey of multi-pollutant design principles and optimal searches for siting patterns of an AQMN using both simulation and optimization models as a combined tool. While conservative, quasi-stable, and reactive pollutants are considered in the design principles, cost, coverage effectiveness, and spatial correlation characteristics are included in the multi-criteria decision making process. For illustrative purpose, a series of technical settings and two types of objectives were examined in the case study for the city of Kaohsiung in Taiwan.     

Preferred surface microscopic geometric features on floors as potential interventions for slip and fall accidents on liquid contaminated surfaces

PROBLEM: Surface roughness affects friction, so selection of floor surfaces with certain roughness characteristics could potentially reduce slip and fall accidents. This article summarizes the preferred surface microscopic geometric features that could increase friction on surfaces covered with liquid contaminants. METHOD: Three types of surface features, represented by the average of the maximum height above the mean line in each cut-off length (R(pm)), the arithmetical average of surface slope (Delta(a)), and the kernel roughness depth (R(k)), are identified as preferred surface microscopic geometric features for a higher friction. The proper settings on the profilometers (instruments used to measure surface roughness) for optimizing these surface parameters are specified. The friction mechanisms involved reveal why these features are more desirable. RESULTS: Although surface roughness is important in determining slipperiness, there is still insufficient information to establish a safety criterion based on roughness; however, the method presented in this paper can readily provide a relative comparison. IMPACT ON INDUSTRY: The summary presented will help safety professionals properly select new floor surfaces or assess existing floors to reduce slip and fall accidents.     

化工反应装置危险性分析模式的研究

从近年来化工企业的安全生产事故可以看出,化工生产由于其自身的特点,具有较大的火灾爆炸危险性,因此,正确地对化工企业生产的危险性进行分析,对准确地评价化工企业的安全生产状况非常重要.针对化工企业的安全生产特点,提出了一种针对化工反应装置的危险性分析模式,不仅考虑了生产原料及工艺设备,同时也对工艺过程进行了危险性分析.应用实例表明,该模式对于化工装置的危险性分析具有较强的针对性和可靠性.     

光纤传感器在个体防护装备上的应用进展

1引言 在战场上,个体防护装备对士兵有效地发挥战斗力和避免伤亡起到关键的作用。现代科学技术在军事领域的广泛应用,使得防护装备突破了传统模式,新一代的单兵防护装备不仅要抵御武器的袭击,而且要避免自然环境、化学试剂、火焰和其他战场灾难的危害,须成为高度智能化的作战服。     

动火作业中的安全现状分析

结合新疆八一钢铁集团实际,对动火作业现状进行分析,提出不足;并结合法规、标准要求以及工作实践,从管理、技术、培训等方面提出动火安全的几点对策.