采用生活垃圾研制烧结砖

该文介绍了用好氧发酵工艺对新鲜生活垃圾进行预处理,用做制砖的原料。制砖工艺采用对辊,双轴搅拌,真空挤出,轮窑烧成等工序,垃圾掺加量为30％～50％,可完全取代内掺材料,节省90％以上的煤炭。     

甲基酚烯酸酯树脂的热裂解机理

研究了以甲基丙烯酸酯端基不饱和取酯树脂为主链,用甲基丙烯酸甲酯取代苯乙烯作为交联剂制成的甲基丙烯酸酯树脂（ＭＡＥＲ）与通用型不饱和聚酯树脂（ＧＵＰＲ）的热裂解机理、燃烧现象。结果表明：ＭＡＥＲ的裂角产物中苯环化合物含量（１４．９％）少于ＧＵＰＲ（７４．５％）。ＭＡＥＲ燃烧时的发烟量和毒性也远低于ＧＵＰＲ。在ＭＡＥＲ中加入三水合氧化铝（ＡＴＨ）后,裂解产物中有毒物质的各类和数量更少,在燃烧时只有少量     

Acute systemic and lung inflammation in C57Bl/6J mice after intratracheal aspiration of particulate matter from small-scale biomass combustion appliances based on old and modern technologies

Inflammation is regarded as an important mechanism behind mortality and morbidity experienced by cardiorespiratory patients exposed to urban air particulate matter (PM). Small-scale biomass combustion is an important source of particulate air pollution. In this study, we investigated association between inflammatory responses and chemical composition of PM₁ emissions from seven different small-scale wood combustion appliances representing old and modern technologies. Healthy C57Bl/6J mice were exposed by intratracheal aspiration to single dose (10?mg/kg) of particulate samples. At 4 and 18?h after the exposure, bronchoalveolar lavage fluid (BALF) as well as serum was collected for subsequent analyses of inflammatory indicators (interleukin (IL)-6, IL-1β, IL-12, and IL-10; tumor necrosis factor-α (TNF-α); keratinocyte-derived chemoattractant (KC), and interferon-γ (IFN-γ)) in multiplexing assay. When the responses to the PM₁ samples were compared on an equal mass basis, the PM from modern technology appliances increased IL-6, KC, and IL-1β levels significantly in BALF at 4 and 18?h after the exposure. In contrast, these responses were seen only at 4?h time point in serum. Increased cytokine concentrations correlated with metal-rich ash related compounds which were more predominant in the modern technology furnaces emissions. These particles induced both local and systemic inflammation. Instead, polycyclic hydrocarbon (PAH) rich PM₁ samples from old technology (OT) evoked only minor inflammatory responses. In conclusion, the combustion technology largely affects the toxicological and chemical characteristics of the emissions. The large mass emissions of old combustion technology should be considered, when evaluating the overall harmfulness between the appliances. However, even the small emissions from modern technologies may pose significant toxic risks.     

Effect of Elemental Powder Size on Foaming Behavior of NiTi Alloy Made by Combustion Synthesis

Nickel titanium (NiTi) foams were made by combustion synthesis of powders with the help of ZrH₂ as foaming agent and TiB₂ as endothermic agent. In this paper, we investigated the effect of elemental powder size on the foaming. The powder size of Ni and Ti affected the ignition temperature of the combustion reaction, cell morphology and microstructure of the foams. The cell morphology of the foams was also modified by the powder size of TiB₂.     

Combustion Synthesis and Photoluminescence Properties of Red-Emitting CaAlSiN3:Eu2+ Phosphor for White-LEDs

A combustion synthesis method has been developed for synthesis of Eu²⁺ doped CaAlSiN₃ phosphor and its photoluminescence properties were investigated. Ca, Al, Si, and Eu₂O₃ powders were used as the Ca, Al, Si and Eu sources. The addition of NaN₃, NH₄Cl and Si₃N₄ powders was found to increase significantly the product yield. These powders were mixed and pressed into a compact, which was then wrapped up with an igniting agent (i.e., Mg+Fe₃O₄). The compact was ignited by electrical heating under a N₂ pressure of ≤1.0 MPa. Effects of these experimental parameters on the product yield were investigated and a reaction mechanism was proposed. The synthesized CaAlSiN₃:Eu²⁺ phosphor absorbs light in the region of 200–600 nm and shows a broad band emission in the region of 500–800 nm due to the 4f⁶5d¹ → 4f⁷ transition of Eu²⁺. The sample doped with Eu²⁺ at the optimized molar ratio of 0.04 is efficiently excited by the blue light (460 nm) and generates emission peaking at ~650 nm with peak emission intensity ~106% of a commercially available phosphor, YAG:Ce³⁺(P46-Y3).The internal quantum efficiency of the synthesized phosphor was measured to be 71%, compared to 69% of the YAG:Ce³⁺ (P46-Y3).     

The Cellular Toxicity of PM2.5 Emitted from Coal Combustion in Human Umbilical Vein Endothelial Cells

ObjectiveTo explore the relationship between different components offineparticulate matter (PM2.5) emitted from coal combustion and their cytotoxic effect in the vascular endothelial cells. MethodsCoal-fired PM2.5was sampled using a fixed-source dilution channel and flow sampler. The sample components were analyzed by ion chromatography and inductively coupled plasma atomic emission spectroscopy(ICP-AES). The PM2.5suspension was extracted using an ultrasonic water-bath method and thenhuman umbilical vein endothelial cells (EA.hy926) were treated withvarious concentrations of the PM2.5 suspension. Cell proliferation,oxidativeDNA damage, and global DNA methylation levelswere used to measurethe cellulartoxicity of PM2.5emitted fromcoalcombustion. ResultsComparedtoothertypesof coal-fired PM2.5preparations,thePM2.5 suspension from Yinchuan coal had the highest cytotoxicity.PM2.5 suspension from Datong coal hadthe highest toxic effectwhile that fromYinchuan coal had the lowest.Exposure to coal-fired PM2.5 from Jingxi coalresulted inlower 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels. At the same dose, PM2.5 emitted from coal combustion could produce more severeDNAimpairmentcompared to that produced by carbon black.Cell survival rate was negatively correlated with chloride and potassiumionscontent.The5-methylcytosine(5-mC) level waspositively correlated withMnandnegatively correlated withZn levels.The 8-OHdG% level was positively correlated withboth MnandFe. ConclusionPM2.5 emitted from coal combustion can decrease cell viability, increase global DNA methylation, and causeoxidativeDNA damage inEA.hy926 cells. Metalcomponentsmay be important factors that influence cellular toxicity.     

Mechanical and Combustion Properties of Agglomerates of Wood of Popular Eastern European Species

The objective of the reported project was to produce wood agglomerates from popular East European species to determine their strength and combustion properties. Closed-die pellets were produced from sawdust of six types of wood common on the East European market: pine, willow, oak, poplar, birch, and beech. The properties of pellets, determined by the type of wood, were influenced by the compaction pressure and the moisture content of the sawdust. The highest average pellet density was obtained for oak sawdust, while the lowest density was obtained for poplar pellets. Expansion of pellets after removing from the die was found to be dependent on the wood species, and as expected, on compaction pressure. The pellet expansion increased after 2 h of conditioning in the laboratory and with an increase in moisture content. The highest and the smallest strength were obtained for oak pellets and for birch sawdust, respectively. The strength of the pellets increased by more than 100% with an increase in the compaction pressure from 60 MPa to 120 MPa. The average strength decreased by 65% with increasing moisture content. For all tested materials, drop resistance remained at a high level, acceptable in industrial practice. The highest calorific value of 18.97 MJ/kg was obtained for pine pellets. The highest ash value of 1.52% was obtained for willow pellets and the lowest value of 0.32% for pine pellets.     

Morphology and Chemical Composition of Magnetic Particles Separated from Coal Fly Ash

Iron and other metal compounds are the materials that often appear in coal seams, because they also appear as a component of former organic matter in coal rocks. Although iron is the dominant element in coal rocks, other metals such as titanium, lead, cobalt, nickel, and copper are also present. In this study, the properties of magnetic particles of a size between 1 and 20 µm of globular structure and iron containing, were separated from coal fly ash, and studied using a scanning electron microscopy, energy disperse spectroscopy, and X-ray diffraction spectroscopy. The investigations were comprised of micrographs of the structure of these particles, their elemental composition, and phase analysis.     

工业锅炉燃烧过程的稳态优化模型

建立了一个以能源成本最低为目标、采用神经网络模拟约束条件的工业锅炉燃烧过程稳态优化模型.介绍了该模型的罚函数法求解算法,并给出了一个应用实例.理论计算和实际使用表明,该模型有相当的精度,可以显著提高系统的能源利用率.     

Combustion Synthesis of Porous TiC/Ti Composite by a Self-Propagating Mode

Porous titanium carbide (TiC) and TiC/Ti composites were synthesized by self-propagating high-temperature synthesis (SHS). Titanium and carbon powders were blended by various Ti/C blending ratios. The heat of reaction between titanium and carbon was high enough to induce the self-sustaining reaction of TiC formation on condition that some processing parameters (Ti/C ratio and porosity of the precursor) were appropriately selected. When the Ti/C blending ratio was high, the excess amount of titanium absorbed the heat of reaction. Consequently, the heated zone was not heated up to the ignition temperature. On the other hand, when the Ti/C ratio was low, high thermal conductivity of the precursor prevented an ignition of the heated side of precursors. The pore morphology was controlled by changing the Ti/C ratio and the preheat temperature.