Temperature Fluctuations Accompanying Water Movement through Porous Media

Temperature measurements were made at localized sites in bentonite, kaolinite, and small glass beads during infiltration. The temperature of the medium was observed to rise gradually and then to drop sharply as the infiltrating water approached and reached the measurement site. Temperature fluctuations were observed to be about 9 degrees C for bentonite, 4 degrees C for kaolinite, and 0.1 degrees C for the glass beads.     

凹土基悬浮滤料制备与性能研究

[目的]研究凹土基悬浮滤料的制备方法与性能特点。[方法]利用凹土、玻璃微珠、粉煤灰漂珠复配制备凹土基悬浮滤料,并测定滤料对废水CODCr及NH+4-N的处理效果。[结果]凹土、玻璃微珠、粉煤灰漂珠适宜添加重量比为5∶3∶3;最佳烧结温度为900℃;制得的滤料密度在0.173~0.921 g/cm3。废水处理试验结果表明,对CODCr处理效果可达95.0%,对NH+4-N处理效果可达95.6%。[结论]制备的凹土基悬浮滤料性能良好,可用于废水的处理。     

Flash hydrogenation of a bituminous coal

Flash heating of Illinois coal (to 700 degrees C in 1 second) in flowing hydrogen at 100 atmospheres, limiting the vapor residence time at 700 degrees C to 3 seconds, converts 14 percent of the coal's carbon to methane, 7 percent to ethane, and 10 percent to benzene, toluene, and xylenes. The remainder is coke; the carbon balance shows that heavy tar, if any exists, is less than 3 percent.     

水平液固循环流化床起旋器的实验研究

在φ29 mm×4 200 mm流化床装置上,利用CCD图像测量与数据处理系统在线对导流叶片式局部起旋器对水平液固循环流化床内固相颗粒分布特性的影响进行了研究。结果表明:安装局部起旋器后,颗粒分布状况在一定距离内得到明显改善;但随着轴向距离增加,起旋器作用效果减弱。随着导叶包角、液体流速的增加,颗粒固含率不均匀度减小。对于相同直径的颗粒,密度和初始加入量越大,颗粒固含率不均匀度越大。     

Erratum

In the report "Mutagenicity of fly ash particles in Paramecium" by J. Smith-Sonneborn et al. (9 Jan., p. 180), Tables 1 and 2 are printed incorrectly. Significance lines are missing from both tables and "uninduced" should read "induced" in the sixth, eighth, and ninth entries of the first column in Table 1. The tables are reprinted below as they should have appeared. Table 1. Mutagenic effect of fly ash and heat-treated fly ash in Paramecium. Values not connected by the same line are significantly different from each other (Wilcoxon matched-pairs signed-ranks test, alpha = .05). The data from six experiments were pooled since the control values for autogamous progeny were not significantly different. Cerophyl is the ryegrass extract used for cultivation of Paramecium. Induced S-9 is the Ames liver microsome fraction from rats receiving Arochlor 1254 (polychlorinated biphenyl) to activate the enzymes for conversion of promutagens to mutagenic form; uninduced S-9 is from rats receiving corn oil only (the vehicle for the Arochlor). Glass beads (1 to 3 ,microm) suspended in either induced or uninduced S-9 were used as a negative control for nonnutritive particles. Kaolinite was also used in one experiment, and the results were the same as those for the glass beads. Benzo[a]pyrene was the positive control for mutagenicity requiring induced S-9. The initial concentration of suspended fly ash was 535 ,microg/ml. The average number of affected progeny from treated parent cells was 20 percent higher than the average number of affected control progeny. Since one mutation would theoretically yield only 4 affected progeny in 16 autogamous progeny from a treated parent cell (6), the percentages, though low, reflect significant damage. [See table in the PDF file] Table 2. Mutagenicity of heat-treated fly ash extracted with HCl or DMSO. Values not connected by the same line are significantly different from each other (pairwise comparisons of proportions, P < .05). The concentration of fly ash particles suspended in uninduced S-9 was 1068 ,ug/ml. The higher than usual value for mutagenicity in the controls can be attributed to the considerable age of the clone used here [micronuclear damage increases with age (12)]. [See table in the PDF file].     

两种生物质原料在流化床中的流化特性研究

[目的]研究两种生物质原料蓝藻与松木在流化床中的流化特性。[方法]利用流化床冷态试验装置,采用降速法,对蓝藻与松木的流化特性进行了对比试验研究。[结果]布风板开孔率、物料粒径、石英砂粒径和石英砂质量比等因素对蓝藻和松木流化质量的影响程度各不相同。蓝藻和松木流化质量最佳的试验条件组合分别为开孔率为2.597%、蓝藻粒径0.20～0.45 mm、石英砂粒径0.20～0.45mm、石英砂质量比80%;开孔率为3.393%、松木粒径0.20 mm、石英砂粒径0.20～0.45 mm、石英砂质量比60%。[结论]该研究为不同种类生物质原料在流化床中热解液化提供了一定依据。     

Model studies of polychlorinated dibenzo-p-dioxin formation during municipal refuse incineration

Toxic chlorinated dibenzo-p-dioxins are known to be formed in incinerators that burn municipal refuse. These compounds were synthesized by surface-catalyzed reactions on fly ash particulates taken from incinerators. Dioxins were produced catalytically from chlorinated phenol precursors, from non-chlorinated compounds that were chemically dissimilar to dioxins, and from reaction of phenol with inorganic chlorides. The relative amounts of dioxins formed from [13C6]pentachlorophenol with different fly ashes that had been cleaned of all organic compounds corresponded well with those amounts originally found on the samples as received from the incinerators. The optimum temperature range for the formation of dioxins from pentachlorophenol was 250 degrees to 350 degrees C.     

粉煤灰充填复垦土壤理化性质分布特征及其对覆土厚度响应

以淮南市平圩电厂粉煤灰堆场复垦区为研究对象,采用经典统计和地统计学相结合的方法,从点和区域、水平与垂直等多维角度分析了不同覆土厚度下的复垦土壤主要理化性质分布特征,旨在揭示粉煤灰充填基质下复垦土壤理化性质分布特征及其与覆土厚度之间的响应关系。结果表明,随着覆土厚度的增加,土壤含水量均值呈现先增后减的趋势,各覆土厚度下土壤含水量基本在20%以上,覆土厚度20～30cm的土壤含水量最大,达到31.11%。在一定的覆土厚度下,含水量在粉煤灰重构剖面中间会出现一个突变层次,在土—灰界面将产生土壤水分的聚集。不同覆土厚度下表层土壤的容重出现明显的差异,随着覆土厚度的增加,土壤容重整体呈现上升趋势,覆土厚度40～60 cm时,土壤表层平均土壤容重达到1.75 g·cm-3,复垦后出现了不同程度的板结现象。不同覆土厚度下砂、粉和黏粒含量差异明显,总体上与该地区非重构土壤相似,基本属于粉砂质壤土。粉煤灰充填复垦后土壤颗粒组成由粉煤灰、覆土土源和覆土方式共同决定的,泥浆泵法覆土在不同水平间土壤颗粒组成差异较为明显。随着覆土厚度的增加,不同层次的有机质含量都有不同程度的提升,且提升程度与覆土厚度呈正相关。基于经验贝叶斯克里格法的复垦土壤含水量、容重、粉砂和有机质含量的RMSE分别为1.72、1.01、1.57和0.85;MSDR值分别为2.12、1.32、2.72和0.62,RMSE较小,预测精度较高,MSDR比较接近1,模型拟合效果较好。综合考虑各理化指标对覆土厚度的响应特征,冬小麦-夏玉米种植模式下覆土厚度40～50cm较为合理。经验贝叶斯克里格法比较适合粉煤灰充填复垦土壤理化指标空间预测。     

施肥对慈竹灰分·苯醇抽出物和木质素含量的影响

[目的]通过农业技术措施从源头上改善灰分、苯醇抽出物和木质素的含量,更好地利用竹资源。[方法]以1年生慈竹为材料,研究不同氮钾配比对慈竹灰分、苯醇抽出物和木质素含量的调控效应。[结果]结果表明:施肥处理慈竹的灰分、苯醇抽出物和木质素的含量与对照处理具有明显的差异。不同处理的灰分、苯醇抽出物含量均较对照有不同程度的升高,而木质素含量则比对照低。施肥处理后慈竹的灰分含量随K肥用量的增加而上升,受N肥用量影响不大。苯醇抽出物含量受N肥、K肥用量影响均不大。木质素含量随着N肥用量的增加逐渐降低,受K肥用量影响不大。处理N200K200木质素含量最低,其次是N200K50。[结论]对于木质素含量与灰分含量变化的协调,需考虑二者在慈竹生理上和利用中的重要性,设计更多不同肥料配比另作研究。     

不同配比的粉煤灰和滤泥对红壤理化性质与大麦产量的影响

在2种旱地红壤上施用不同质量配比的粉煤灰和滤泥混合物,研究其对红壤改土和大麦增产的效果.结果表明:施用不同质量配比的该混合物后土壤酸性均明显减弱;速效NPK、>0.25mm微团聚体含量及比磁化率都有不同程度的提高;大麦根系重量、生物产量和经济产量均显著提高,根系重量和生物产量均随混合物中滤泥比例的提高而提高,而经济产量则以施用"20%粉煤灰+80%滤泥"的处理最高,其经济产量与其它各处理的差异均达显著或极显著水平,表明施用"20%粉煤灰+80%滤泥"混合物对供试土壤的改土和大麦的增产,效果较为显著.     

Antarctic ice sheet: preliminary results of first core hole to bedrock

The Antarctic ice sheet at Byrd Station has been core-drilled to bedrock; the vertical thickness of the ice is 2164 meters. Liquid water-indicative of pressure melting-was encountered at the bed. Heat flow through the base of the ice sheet is estimated at 1.8 microcalories per square centimeter per second. The minimum temperature was -28.8 degrees C at 800 meters; maximum ice density, 0.9206 at 1000 meters. Core studies reveal the existence of a chemically pure, structurally stratified sheet comprising bubbly ice to 900 meters that transforms to bubble-free deformed ice, with substantially vertically orientated c-axis structure, below 1200 meters. Below 1800 meters the deformed ice structure gives way to large annealed crystals. Several thin layers of dirt between 1300 and 1700 meters are tentatively identified as volcanic ash, and horizontally banded debris, including fragments of granite, is present in the basal ice.     

Late Twilight Glow of the Ash Stratum from the Eruption of Agung Volcano

Observation of the height of the dust layer responsible for the onset of brilliant sunsets in the 30 degrees N zone since September 1963 gives evidence that the ash has diffused from the eruption of the volcano Agung on Bali. A height of 22 km is derived for the top of the primary stratum.     

Meteorological analysis of the eruption of soufriere in april 1979

Meteorological upper-air data, in conjunction with satellite imagery, lidar light detection and ranging returns, and aircraft sampling, aid in the determination of plume altitude and transport. The estimated trajectories indicate that the ash was transported eastward across the Atlantic to Africa in 3 to 5 days and that there was modest meridional transport as far as 15 degrees poleward during the first week of travel.     

粉煤灰对加工番茄生长与养分吸收的影响及对春小麦残效研究

[目的]揭示石灰性土壤施用碱性粉煤灰与作物生长和元素吸收的关系.[方法]分别以加工番茄和春小麦为材料,采用盆栽试验研究干旱区灌耕灰漠土施用粉煤灰对加工番茄生长及养分吸收的影响,并以春小麦为二茬作物研究粉煤灰的残效作用.[结果]施用粉煤灰可以增加加工番茄地上部干物质量,同时增加花期叶片氮含量,减少茎秆和叶片磷含量;但是增加收获期叶片氮、磷、钾的含量.同时施用粉煤灰增加加工番茄花期茎秆、叶片和植株整体的氮、钾的积累量,而减少加工番茄茎秆、叶片和植株整体磷的积累量;施用粉煤灰增加加工番茄收获期茎秆、叶片和植株的氮、磷、钾的积累量.残效试验表明,与对照相比,粉煤灰残效显著提高春小麦地上部干物质量,减少春小麦花期茎秆和叶片氮、磷、钾含量;22.50t/hm2粉煤灰残效增加春小麦收获期茎秆和叶片的氮、磷、钾含量.粉煤灰残效增加春小麦花期茎秆、叶片和植株氮和钾积累量和叶片、植株磷的积累量;增加春小麦收获期茎秆,叶片和植株氮、磷、钾积累量.粉煤灰及其残效作用增加土壤pH值和电导率.[结论]使用粉煤灰可以增加收获期加工番茄和春小麦地上部干物质积累量和氮、磷、钾积累量,同时增加土壤pH值和电导率.     

卷烟降焦技术的研究进展

焦油是烟草产品燃烧时主要的危害物之一,对于烟草的降焦减害是整个烟草行业关注的焦点。本文从烟丝降焦、滤嘴降焦和烟纸降焦3个方面介绍了国内外近几年的各种降焦方法及特点,分析了各种降焦方法的作用原理及效果,并提出了未来的发展方向。     

Subaqueous explosive eruption and welding of pyroclastic deposits

Silicic tuffs infilling an ancient submarine caldera, at Mineral King in California, show microscopic fabrics indicative of welding of glass shards and pumice at temperatures >500 degrees C. The occurrence indicates that subaqueous explosive eruption and emplacement of pyroclastic materials can occur without substantial admixture of the ambient water, which would cause chilling. Intracaldera progressive aggradation of pumice and ash from a thick, fast-moving pyroclastic flow occurred during a short-lived explosive eruption of approximately 26 cubic kilometers of magma in water >/=150 meters deep. The thickness, high velocity, and abundant fine material of the erupted gas-solids mixture prevented substantial incorporation of ambient water into the flow. Stripping of pyroclasts from upper surfaces of subaqueous pyroclastic flows in general, both above the vent and along any flow path, may be the main process giving rise to buoyant-convective subaqueous eruption columns and attendant fallout deposits.     

煤球灰对磷的吸附特性研究

[目的]探讨煤球灰对磷的吸附特性。[方法]以餐饮业煤球燃烧后的煤球灰为试材,研究煤球灰对磷的吸附动力学过程、等温吸附以及一些因素对煤球灰吸附磷的影响。[结果]在吸附的初始阶段（0～2h）,煤球灰对磷的吸附量上升很快,此后趋于平缓;煤球灰吸附磷过程中,系统的△G0〈0,△H0〉0,说明煤球灰对磷的吸附作用是一个自发的、吸热过程;煤球灰对磷的等温吸附可用Langmuir和Temkin等温模型拟合,相关性均达极显著水平,由Langmuir等温方程计算的最大吸附量Qm为1250mg/kg;在酸性条件下,随着溶液pH值的上升,煤球灰对磷的吸附量降低,在碱性条件下,吸附量趋于平衡;低分子有机酸对磷吸附有抑制作用,对饱和磷释放有促进作用。[结论]煤球灰对磷吸附的动力学特征能很好地遵循准二级动力学模型。     

立地条件对落叶松和水曲柳带状混交效应的影响

以天然次生林皆伐迹地人工更新的７年生落叶松和水曲柳混交林带对对象，研究了不同坡位对叶松与水曲柳带状混交相互关系的影响。由于坡位不同，各项生态因子发生变异致使落松对水曲柳影响表现不一致。在早期，落叶松与水曲柳之间朱接触以前，水曲柳地上的生长主要受环境因子的影响。落叶松对水曲柳生长的首先表面在根系上，然后反映到地上部分。     

包埋玻璃化法超低温保存沙生柽柳休眠茎尖的研究

[目的]采用包埋玻璃化法,对沙生柽柳休眠茎尖成功地进行冷冻保存。[方法]将沙生柽柳休眠茎尖包埋在含3%褐藻酸钙的胶球中,研究了预培养中蔗糖浓度、培养时间和不同玻璃化保护液处理的时间对沙生柽柳休眠茎尖存活率的影响。[结果]含沙生柽柳茎尖的胶球在0.8mol/L蔗糖溶液中培养24h可获得较高的存活率;胶球经玻璃化保护液[40%甘油＋45%（0.4mol/L）蔗糖＋10%聚乙二醇（分子量4000）＋5%二甲基亚砜]在25℃处理20min可以明显提高存活率,在优化条件下存活率可高达48.3%。[结论]蔗糖浓度和预培养时间是决定沙生柽柳茎尖存活率的关键因素。     

内包粉末活性炭凝胶球去除苯酚

研究了不同包埋材料包埋的粉末活性炭凝胶球在中性条件下对苯酚和腐殖酸的吸附效率和苯酚的吸附等温线。结果表明:内包粉末活性炭凝胶球对苯酚的吸附等温线符合Freundlich方程,以海藻酸钠,聚乙烯醇海藻酸钠为包埋材料的凝胶球吸附苯酚的性能优于经缩醛反应后的聚乙烯醇海藻酸钠为包埋材料的凝胶球。凝胶球减少了粉末活性炭对水体中腐殖物质的吸附,添加聚乙烯醇增加了凝胶球的机械强度,不易粘连。添加戊二醛进行缩醛反应使得凝胶球网状结构致密,导致吸附苯酚能力下降,但不吸附腐殖酸,具有选择性吸附的性质。