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41.
黏土水泥浆材是采空区处治的优选注浆材料,但目前关于优化浆材配比的研究较少。针对毕威高速公路水塘隧道出口段采空区处治工程,提出采用黏土水泥浆液进行注浆处理,并进行室内试验研究,得到了不同配比浆液的凝结时间、结石率、结石密度、结石体抗压强度、渗透系数及冲蚀率等性能指标。试验结果表明,固相比较低的浆液凝结时间较短,抗压强度较高,渗透系数较大;随原浆比重增加,浆液的凝结时间缩短,强度提高且渗透系数降低;偏铝酸钠可有效缩短浆液的凝结时间;最终确定了黏土水泥浆材的配比和原浆比重。本次研究可为高速公路下伏采空区的注浆治理提供设计依据。 相似文献
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Lin He Song Wang Xiao-Jie Xu Roberto Soria Ji-Feng Liu Xiang-Dong Li Yu Bai Zhong-Rui Bai Jin-Cheng Guo Yan-Li Qiu Yong Zhang Ruo-Chuan Xu Ke-Cheng Qian 《天文和天体物理学研究(英文版)》2019,(7)
X-ray emission is an important indicator of stellar activity. In this paper, we study stellar Xray activity using the XMM-Newton and LAMOST data for different types of stars. We provide a sample including 1259 X-ray-emitting stars, of which 1090 have accurate stellar parameter estimations. Our sample size is much larger than those used in previous works. We find a bimodal distribution of the X-ray to optical flux ratio(log(fX/fV)) for G and K stars. We interpret that this bimodality is due to two subpopulations with different coronal heating rates. Furthermore, using the full widths at half maxima calculated from Hα and Hβ lines, we show that these stars in the inactive peaks have smaller rotational velocities. This is consistent with the magnetic dynamo theory that presumes stars with low rotational velocities have low levels of stellar activity. We also examine the correlation between log(fX/fV) and luminosity of the excess emission in the Hα line, and find a tight relation between the coronal and chromospheric activity indicators. 相似文献
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Xianzhong Cheng Kun Shao Shangyue Shen Shenghong Hu Haiou Qiu 《Geostandards and Geoanalytical Research》2011,35(4):461-469
A rapid and inexpensive method was developed for the determination of trace silver in polymetallic ore samples by use of eggshell membrane (ESM), a natural biomaterial, as the solid‐phase extraction (SPE) adsorbent coupled with flame atomic absorption spectrometry (FAAS). The ESM was used for the separation/pre‐concentration of silver, and the parameters affecting sensitivity, such as pH, sample flow rate, eluent volume and eluent flow rate, were carefully investigated. ESM was found to be an effective solid phase extractant for the adsorption of trace silver over a wide range of acidity from 0.02 to 0.50 mol l?1 HNO3. The sample solution in 0.4 mol l?1 HNO3 was pumped through an ESM microcolumn at the rate of 1.0 ml min?1. Silver was absorbed, and then eluted with a solution of 1.0% m/v thiourea–0.5% v/v HCl. Under these optimal conditions, ESM exhibited a good enrichment efficiency for silver with a dynamic adsorption capacity of 1.7 mg g?1. The proposed method was applied to the FAAS determination of trace silver in polymetallic ores and geological reference materials, GSO‐2, 3 and 5, and GSD‐11, GSD‐12, and the determined values were in good agreement with certified values. 相似文献
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突出山铜铁矿床是东天山雅满苏石炭纪弧前-岛弧带中代表性的铁多金属矿床, 矿体呈透镜状、脉状、似层状赋存于上石炭统底坎尔组下亚组火山岩中。矽卡岩阶段包裹体均一温度为151℃~>380℃, 盐度为1.91%~23.18% NaCleq, 密度为0.76~1.09 g/cm3, 热液硫化物阶段包裹体均一温度为101℃~280℃, 盐度为0.35%~23.05% NaCleq, 密度为0.74~1.13 g/cm3, 表明成矿流体属于中-高温、中-低盐度、中-低密度的NaCl-H2O体系。(绿泥石)绿帘石矽卡岩、磁铁矿(镜铁矿)矿石、含磁铁矿灰岩的稀土配分模式均为轻稀土相对富集的右倾型(LREE/HREE=2.85~9.21), 以出现负铕异常(δEu=0.22~1.09)和铈异常不发育为特征, 与底坎尔组火山岩相似, 表明成矿物质来源于底坎尔组火山岩。矿区矽卡岩可能是火山热液交代碳酸盐岩形成的, 成矿条件为中-高温、较为宽广的氧化还原环境, 矿床成因属火山热液交代型。 相似文献
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扬子陆核崆岭高级变质地体内出露一套强变形的基性-超基性岩岩石组合, 主要呈似层状、透镜状分布于崆岭群中, 该套变基性-超基性岩组合对扬子陆块早期构造演化过程具有重要意义.通过同位素稀释法(isotope dilution thermal ionization mass spectrometry, 简称ID-TIMS)获得该套岩石组合中蛇纹石化方辉橄榄岩全岩Sm-Nd等时线年龄为1063±12Ma, 说明Sm-Nd同位素体系可用于对超低含量、发生强蚀变作用的超基性岩样品进行定年.样品Nd同位素组成相对均一(εNd(t)值为6.90~7.32), 表明形成于封闭体系中, 其对应Nd同位素两阶段模式年龄为1.13~1.09Ga, 与形成年龄接近, 说明来自亏损软流圈地幔部分熔融.结合区域上已有的中元古代末期到新元古代早期构造岩浆事件研究, 认为在该时期扬子陆块可能由多个微陆块组成, 就扬子陆核而言, 其与扬子陆块西侧之间很可能存在分隔的大洋. 相似文献
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利用2013年台风“苏力”的监测资料、台风灾情资料、2000年后福建省台风灾害数据库资料和台风“苏力”灾害防御行为效益评估网络问卷调查资料,采用相似分析法的上下限区间估算法,预评估台风“苏力”造成的受灾人口和直接经济损失,并利用台风灾害风险区划方法,对台风“苏力”进行灾害风险区划。结果表明:台风“苏力”预评估结果与实际灾情相符,台风“苏力”灾害风险分布与实际灾情分布大部分一致,风险等级高的县市,实际灾情重,高风险区的大部县市直接经济损失均为1000万元以上。应用台风灾害防御行为效益评估三级指标体系,通过调查统计分析可知,指标体系中的各级各项指数均能较好地反映和评估政府主导、部门联动和公众参与的防御行为效益,政府主导在各类减灾行为中作用最大。 相似文献
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Patinopecten yessoensis is a commercial valuable species. This study deals with the effect of nutrient effects of the broodstock(mainly ovaries) on the larvae. Concentrations of total carbohydrate, total protein and total lipid in the gonads of P. yessoensis from three Hatcheries(Hatchery 1, Hatchery 2, and Hatchery 3) were determined before and after spawning. The relationship between the nutrient concentration in ovaries before spawning(BC) and that of larvae(LC) was assessed as well as the change in nutrient levels in ovaries after spawning(DC). Results indicate that the BC of total carbohydrate(7.66%) and total lipid(14.48%) in ovaries were significantly higher than in testes(5.20%, 5.20% respectively), whereas the BC of total protein in the ovaries was lower(61.76%) than in the testes(81.67%). The different gonadal composition suggests the different nutrient demands between male and female broodstocks in breeding season. P atinopecten yessoensis gonads contained a higher proportion of lipids, in comparison to other bivalves, which might be a response to the low ambient water temperatures. Further analysis of fatty acids showed that the concentrations of n-3PUFA, EPA and DHA in larvae(LC) were positively correlated with BC and DC, indicating the significant nutrient influence of broodstocks on the larvae. As these fatty acids are important in metabolism, and have been demonstrated to be influential to the viability of the larvae, larval growth and the settlement, spat growth, and juvenile survival in many bivalves, they could possibly be used as indexes to evaluate, and predict condition of broodstocks and larvae. 相似文献