Characteristics of large cooking oil pool fires and their extinguishment by water mist

Large cooking oil pool fires, occurring in industrial oil cookers, present a severe hazard to food processing plants due to their size and the large amount of hot oil involved. This paper reports a series of full-scale fire experiments conducted in a large industrial oil cooker mock-up. The characteristics of large cooking oil pool fires and the effect of oil depth and hood position in the oil cooker on fire growth were studied. The use of water mist for extinguishing large oil pool fires and their extinguishing performance under different discharge pressure and with different types of water mist systems were investigated. Experimental results showed that the cooking oil underwent a substantial expansion in volume during heating. The fires developed quickly once the oil auto-ignited. The fire growth rate was affected by the oil depth in the pan and the hood position in the oil cooker. The water mist fire suppression systems effectively extinguished large cooking oil fires and prevented them from re-igniting. Their extinguishing performance was determined by the type of water mist system, discharge pressure and hood position in the oil cooker.     

用环己烷氧化副产物制备浮选剂

在固体酸催化剂作用下，用环己烷氧化制备环己酮的副产物——酸性油和轻质油进行酯化反应，制备了羧酸混合酯，酯化反应的最佳工艺条件：n（C4-C5醇）：n（有机羧酸）=1．2：1，催化剂质量分数为1．5％，反应温度为110-160℃，反应时间为5h。经应用评价结果表明，该羧酸混合酯是一种性能优异的选煤浮选剂。     

仪化热电厂提高循环水浓缩倍率的措施

针对仪化热电厂将循环水用作冲灰水，导致浓缩倍率只有1.6，以及凝汽器铜管腐蚀结垢严重等问题，提出了隔断循环水与冲灰水的直接联系，实现闲路循环，对凝汽器铜管进行酸洗，并对循环水实施加缓蚀阻垢荆、杀菌剂和旁流过滤等办法，全部实施后产生了很好的效益，值得借鉴。     

玉米芯为碳源实现酸性矿山废水生物处理

引入了一种新的碳源——玉米芯，对SRB法处理酸性矿山废水进行了更加深入的探索，分析了各种参数条件对s暖一还原效果的影响，确定了常温下这种碳源所需要的最适宜工况条件，探讨了硫酸盐矿山废水的水质资源化问题，并对山西矿山废水的生物治理进行了可行性实验验证。实验证明，玉米芯为碳源时，矿山废水中SO^2-4的出水值可达221．1mg／L，金属离子的浓度也都达到了生活饮用水的质量标准，所以玉米芯可作为酸性矿山废水资源化生物处理的合适有效碳源。     

O2-Fenton试剂处理对氨基苯磺酸废水的探讨

利用由O2和Fenton试剂组成的类Fenton系统处理对氨基苯磺酸废水,取得了很好的降解效果.当FeSO4(10g/L)投加量为1.2mL、H2O2(3%)投加量为3mL时,COD去除率可达到70%.     

Mechanical and Barrier Properties of Biodegradable Films Made from Chitosan and Poly (Lactic Acid) Blends

Biodegradable film blends of chitosan with poly(lactic acid) (PLA) were prepared by solution mixing and film casting. The main goal of these blends is to improve the water vapor barrier of chitosan by blending it with a hydrophobic biodegradable polymer from renewable resources. Mechanical properties of obtained films were assessed by tensile test. Thermal properties, water barrier properties, and water sensitivity were studied by differential scanning calorimeter analysis, water vapor permeability measurements, and surface-angle contact tests, respectively. The incorporation of PLA to chitosan improved the water barrier properties and decreased the water sensitivity of chitosan film. However, the tensile strength and elastic modulus of chitosan decreased with the addition of PLA. Mechanical and thermal properties revealed that chitosan and PLA blends are incompatible, consistent with the results of Fourier transform infrared (FTIR) analysis that showed the absence of specific interaction between chitosan and PLA.     

金沙江对硫酸的缓冲性能分析

本文分析了金沙江对硫酸的缓冲特征，建立了江水的缓冲曲线方程，并且验证了此方程的有效性，证明用此方程预测硫酸进入金沙江后江水pH值的变化情况，其预测准确度在0.2个pH单位内。     

细水雾阻隔火焰热辐射的模拟研究

从热辐射传递方程出发，根据Mie散射理论,考虑雾滴对热辐射的散射和吸收特性，建立细水雾阻隔火焰热辐射的两通量模型，并给出简化算法；同时建立小尺度模拟实验系统，对理论模型进行验证。结果表明，两通量模型较为合理地预测了细水雾对火焰热辐射的衰减作用。在此基础上，应用上述理论模型进一步探讨火焰温度、细水雾特性参数、雾场厚度对阻隔热辐射效率的影响，为细水雾系统的实际工程应用提供了理论和依据。     

树脂相分光光度法测定水中痕量苦味酸

建立了树脂相分光光度法测定水中痕量苦味酸的新方法。该法灵敏度高,表观摩尔吸光系数为1.08×105L/(mol·cm);精密度理想(测定苦味酸质量浓度为5μg/mL的实验5次,相对标准偏差为1.0%);线性范围为0～7.0μg/mL;以3σ衡量,检出限为0.14μg/mL;加标回收率为97%～103%。采用该法直接测定水样中的苦味酸、间接测定烟草中的烟碱,结果令人满意。     

Experimental study on the synergistic inhibition effect of nitrogen and ultrafine water mist on gas explosion in a vented duct

In this study, in order to research the synergistic inhibition effect of nitrogen and ultrafine water mist on gas explosion in a vented duct, a semi-confined transparent chamber was designed with the size of 120 × 120 × 840 mm, and the experiments were carried out with stoichiometric methane/air premixed mixture (fraction of methane: 9.5%), adding different fractions of nitrogen and ultrafine water mist. The experimental results showed the following: The combination of nitrogen and ultrafine water mist had a synergistic inhibiting effect on methane/air explosion, which was preferable to the single use of any kind. With the increase of spraying time of water mist and fraction of nitrogen, the initial shape of the explosion flame became snakelike, and at the same time the peak flame propagation speed and peak overpressure decreased significantly. When the nitrogen fraction was increased to 10% and the mist spraying time was increased to 2min, synergistic inhibiting effect on overpressure was high efficient. However, with the increase of spraying time of water mist and fraction of nitrogen going on, the amount of increase of explosion inhibition efficiency was gradually reduced.