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Integration of Tracer Test Data to Refine Geostatistical Hydraulic Conductivity Fields Using Sequential Self-Calibration Method 被引量:5
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作者 胡晓农 蒋小伟 万力 《Journal of China University of Geosciences》 SCIE CSCD 2007年第3期242-256,共15页
On the basis of local measurements of hydraulic conductivity, geostatistical methods have been found to be useful in heterogeneity characterization of a hydraulic conductivity field on a regional scale. However, the m... On the basis of local measurements of hydraulic conductivity, geostatistical methods have been found to be useful in heterogeneity characterization of a hydraulic conductivity field on a regional scale. However, the methods are not suited to directly integrate dynamic production data, such as, hydraulic head and solute concentration, into the study of conductivity distribution. These data, which record the flow and transport processes in the medium, are closely related to the spatial distribution of hydraulic conductivity. In this study, a three-dimensional gradient-based inverse method--the sequential self-calibration (SSC) method--is developed to calibrate a hydraulic conductivity field, initially generated by a geostatistical simulation method, conditioned on tracer test results. The SSC method can honor both local hydraulic conductivity measurements and tracer test data. The mismatch between the simulated hydraulic conductivity field and the reference true one, measured by its mean square error (MSE), is reduced through the SSC conditional study. In comparison with the unconditional results, the SSC conditional study creates the mean breakthrough curve much closer to the reference true curve, and significantly reduces the prediction uncertainty of the solute transport in the observed locations. Further, the reduction of uncertainty is spatially dependent, which indicates that good locations, geological structure, and boundary conditions will affect the efficiency of the SSC study results. 展开更多
关键词 sequential self-calibration tracer test hydraulic conductivity geostatistical simulation inverse problem
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Pilot Test Conducted for Thermal Recoveryof Viscous Crude in Baisc Basin
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《China Oil & Gas》 CAS 1997年第1期38-38,共1页
关键词 test Pilot test conducted for Thermal Recoveryof Viscous Crude in Baisc Basin
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SJ-9A/B Satellites Conduct Key Technology Tests
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作者 Jiang Xueying 《Aerospace China》 2012年第4期9-10,共2页
On October 14, two satellites SJ-9A/B were sent into their preset orbits by a LM-2C/SMA launch vehicle, which is the first flight of a series of China's civilian technology experimental satellites. SJ-9A and B are... On October 14, two satellites SJ-9A/B were sent into their preset orbits by a LM-2C/SMA launch vehicle, which is the first flight of a series of China's civilian technology experimental satellites. SJ-9A and B are the first two satellites in the series of civilian technology experimental satellites designed for tests such as long lifetime and high reliability, high precision and high performance of satellite, domestically developed core components, satellite formation 展开更多
关键词 HIGH SJ-9A/B Satellites conduct Key Technology tests DFH
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基于Aquifer Test的底板放水试验参数计算与评价研究 被引量:7
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作者 田增林 黄选明 +1 位作者 曹海东 李德彬 《煤炭工程》 北大核心 2018年第9期96-100,共5页
为了提高放水试验参数计算的精度和速度,基于地面抽水试验和井下底板放水试验在水文地质参数计算中的相似性,将抽水试验中常用的Aquifer Test求参软件用于宁东灵新煤矿底板承压含水层放水试验的参数求解中,分别采用了标准曲线对比法、... 为了提高放水试验参数计算的精度和速度,基于地面抽水试验和井下底板放水试验在水文地质参数计算中的相似性,将抽水试验中常用的Aquifer Test求参软件用于宁东灵新煤矿底板承压含水层放水试验的参数求解中,分别采用了标准曲线对比法、直线图解法和水位恢复法对渗透系数K和贮水系数μ*进行了拟合求解,并和手工方式下的计算过程及结果进行了对比和分析。结果显示,采用手工和软件计算所得参数的平均值总体上无较大差异,但手工方式在不同方法下的拟合结果存在较大的离散性和不确定性,而Aquifer Test软件由于融合了人工拟合和机器拟合两者的优势,所得结果精度显著高于前者,同时较前者具有操作过程简易、计算结果同步等优点,适合在有多个观测孔的底板放水试验参数计算中推广应用。 展开更多
关键词 AQUIFER test 底板放水试验 水文地质参数 渗透系数 贮水系数
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Development and application of WGQ type micro-computer-based electromagnetic nondestructive testing instrument for quality of metal material 被引量:2
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作者 万静 何云斌 +1 位作者 樊景云 万国庆 《中国有色金属学会会刊:英文版》 CSCD 2002年第6期1058-1062,共5页
The WGQ type micro computer based electromagnetic nondestructive testing instrument for quality of metal material was developed on the principle of electromagnetic induction. The invention and marketing of the WGQ ins... The WGQ type micro computer based electromagnetic nondestructive testing instrument for quality of metal material was developed on the principle of electromagnetic induction. The invention and marketing of the WGQ instrument has solved the world wide tough problem of the "N" shape relation between the indicated values of testing instruments and the hardness of most metal parts, particularly steel and iron parts. It has also greatly improved the hardness testing precision of aluminium alloy. Consequently the instrument can accurately perform either the quantitative testing of aluminium alloy, steel and iron parts hardness or the qualitative testing of their internal and external defects such as cracks, over burnt and so on. Its hardness testing precision is HRB±0.7, HRC±1 and HB±10. The testing speed can reach 1 500 parts per hour. The instrument has already been successfully applied to the spot of lots of factories. 展开更多
关键词 硬度 电磁非破坏性测试 磁导 电导率
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Numerical analysis on thermal conductivity of poly-mineral rock 被引量:1
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作者 Huimin Jing Xiangwei Yu Huai Zhang Yaolin Shi 《Earthquake Science》 CSCD 2010年第3期223-232,共10页
In order to explore the thermal conductivity of the natural poly-mineral rock,numerical tests of rock models with randomly-distributed components were conducted and compared with each other.Elaborately designed Monte ... In order to explore the thermal conductivity of the natural poly-mineral rock,numerical tests of rock models with randomly-distributed components were conducted and compared with each other.Elaborately designed Monte Carlo method was adopted to ingratiate the requirement of the random characteristics of grain size and the grains'spatial distribution.This requirement was fulfilled by clustering the randomly generated unstructured tetrahedral elements in full three dimensions.Natural rocks are consisted of randomly distributed crystal particles or intergranular minerals.Our primary results verify that the thermal conductivity of the rock is strongly sensitive to the ingredients' volume fraction and their spatial distribution.Furthermore,we proved that,in order to reduce the measurement error to a reasonable range,the numerical specimen must be large enough or include sufficient number of mineral particles.Our numerical test results are in accordance with a variety of empirical formulas which are currently employed in petrology. 展开更多
关键词 thermal conductivity poly-mineral numerical test finite element method
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The Study of Electromagnetic Stress Testing Method on Oil-Gas Pipelines Based on WT 被引量:7
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作者 Bin Liu Wanru Sun Yiren Lin 《Geomaterials》 2014年第2期55-63,共9页
This paper proposes an effective method for early diagnosis (stress concentrating) of the oil-gas pipeline. Based on the principle of electromagnetic induction Faraday, we have designed and realized the nondestructive... This paper proposes an effective method for early diagnosis (stress concentrating) of the oil-gas pipeline. Based on the principle of electromagnetic induction Faraday, we have designed and realized the nondestructive testing system for stress concentration area of ferromagnetic materials by means of the research of metal materials inverse magnetostrictive effect mechanism. The system changes the influence degree of the stress in ferromagnetic materials’ magnetic conductance to the corresponding voltage array by using discrete wavelet analysis method to process the data, in which not only the measuring accuracy is improved, but also the stress concentration is more directly reflected. The experiments confirm that the electromagnetic stress testing method is feasible and valid. 展开更多
关键词 Oil-Gas PIPELINE Electromagnetic INDUCTION Magnetic conductANCE Stress CONCENTRATION NONDESTRUCTIVE testing
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Experimental Analysis of Hydraulic Conductivity for Saturated Granular Soils
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作者 Ahlinhan Marx Ferdinand Djenou B. Dorothée Adjovi Edmond Codjo 《Geomaterials》 2023年第3期71-90,共20页
Hydraulic conductivity is the ability of a porous media to transfer water through its pore matrix. That is a key parameter for the design and analysis of soil fluid associated structures and issues. This paper present... Hydraulic conductivity is the ability of a porous media to transfer water through its pore matrix. That is a key parameter for the design and analysis of soil fluid associated structures and issues. This paper presents the test results of the vertical hydraulic conductivity k<sub>v</sub><sub> </sub>carried out on one poorly graded sand and three gap graded gravely sand. It was found that the vertical hydraulic conductivity of saturated soil depends on the grain size distribution curve, on the initial relative density of the soil. Compilation of these current test results and other test results published, shows that the common approaches predict well to some extent the vertical hydraulic conductivity k<sub>v</sub> for the poorly graded sand materials and underestimate the k<sub>v</sub> values for gap graded gravely sand materials. Therefore, new approaches are developed for the prediction of the vertical hydraulic conductivity in saturated poorly graded sand and gap graded gravely sand. The derived results from the new approaches lie in the range of the recommended values by (EAU 2012) and (NAVFAC DM 7 1974). 展开更多
关键词 PERMEABILITY Hydraulic conductivity testS Saturated Granular Soils Prediction Approaches
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Column test-based features analysis of clogging in artificial recharge of groundwater in Beijing 被引量:1
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作者 NAN Tian SHAO Jing-li CUI Ya-li 《Journal of Groundwater Science and Engineering》 2016年第2期88-95,共8页
With the completion of South-North Water Transfer Project in China, plenty of high quality water will be transported to Beijing. To restore the groundwater level in Beijing, part of transferred water is planned to be ... With the completion of South-North Water Transfer Project in China, plenty of high quality water will be transported to Beijing. To restore the groundwater level in Beijing, part of transferred water is planned to be used for artificial recharge. Clogging is an unavoidable challenge in the artificial recharge process. Therefore, a test is designed to analyse clogging duration and scope of influence and to test the reinjection properties of different recharge media. The test employs the self-designed sand column system with variable spacing and section monitoring, composed of four parts: Sand column, water-supply system, pressure-test system and flow-test system, to simulate the clogging of artificial recharge of sand and gravel pits. The hydraulic conductivity levels of all sand column sections are obtained to analyse the clogging of the injection of different concentrations in media of different particle sizes. In this experiment, two kinds of media are used–round gravel from sand and gravel pit in Xihuang village and the sand from sand and gravel pit by the Yongding River. The concentrations of recharge fluid are respectively 0.5 g/L and 1 g/L. The results show that clogging usually lasts for 20 hrs., and the hydraulic conductivity drops to the original 10%. Clogging usually occurs at 0–12 cm section of the sand column. The scope of influence is 0–60 cm. In column 3 and 4, whose average particle sizes are larger, section 20–50 cm also suffers from clogging, apart from section 0–12 cm. The effective recharge times are respectively 33 hrs. in column 1, 14 hrs. in column 2, 12 hrs. in column 3 and 12 hrs. in column 4. The larger the average particle size is, the quicker the clogging occurs. In media of larger particles, the change in suspension concentration does not have significant influence on the development of clogging. In conclusion, it is suggested that during artificial recharge, the conditions of reinjection medium should be fully considered and effective method of recharge be employed in order to improve effective recharge time. 展开更多
关键词 Recharge clogging test Recharge conditions Hydraulic conductivity Clogging scope of influence Clogging rate
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儿童分泌性中耳炎共振频率特征研究及其诊断效能
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作者 汪倩 孔维丽 郑芸 《中国眼耳鼻喉科杂志》 2024年第5期423-426,共4页
目的 探索分泌性中耳炎(OME)和健康儿童之间中耳共振频率(RF)的差异,以及RF、气骨导差、峰值处鼓室压、峰补偿静态声导纳对儿童OME的诊断效能。方法 2018年7月—2019年3月收治的OME患儿为OME组,同期健康儿童为对照组,均行声导抗测试和... 目的 探索分泌性中耳炎(OME)和健康儿童之间中耳共振频率(RF)的差异,以及RF、气骨导差、峰值处鼓室压、峰补偿静态声导纳对儿童OME的诊断效能。方法 2018年7月—2019年3月收治的OME患儿为OME组,同期健康儿童为对照组,均行声导抗测试和纯音测听,记录并对比分析测试结果。结果 OME组的RF为(720.00±353.60)Hz,与对照组的(932.19±318.69)Hz比较差异均具有统计学意义(P <0.01)。OME组的气骨导差、峰补偿静态声导纳、外耳道容积、中耳RF、峰值处鼓室压与对照组相比差异均具有统计学意义,OME组中气骨导差、峰值处鼓室压、峰补偿静态声导纳、中耳RF的受试者操作特征曲线(ROC曲线)的曲线下面积分别为0.92、0.91、0.69、0.68。结论 OME患儿中耳RF降低,但其诊断效能一般,故RF需与纯音测听、声导抗测试结合,增加OME的检出率。 展开更多
关键词 分泌性中耳炎 中耳共振频率 声导抗测试
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Groundwater Potentials Estimation of a Basement Terrain Using Pumping Test Data for Parts of Sanga Local Government Area, Kaduna State, Northwestern Nigeria
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作者 Hamidu Hassan Sidi Muhammad Waru +1 位作者 Garga Ali Bukar Kana Muhammad Abdullahi 《Open Journal of Modern Hydrology》 2016年第4期222-229,共8页
Aquifers derived from the crystalline basement rocks for parts of Sanga Local Government area of Kaduna State, Nigeria consist of clay, silt, sand, gravel and laterite materials which may be in various proportions. Us... Aquifers derived from the crystalline basement rocks for parts of Sanga Local Government area of Kaduna State, Nigeria consist of clay, silt, sand, gravel and laterite materials which may be in various proportions. Using Cooper-Jacobs non-equilibrium graphical method, the hydraulic properties were estimated from pumping test data of 18 boreholes. Conductivity varies from 1.02 × 10<sup>﹣2</sup> m/s to 4.07 × 10<sup>﹣2</sup> m/s and transmissivity varies from 1.14 × 10<sup>﹣1</sup> m<sup>2</sup>/s to 4.40 × 10<sup>﹣1</sup> m<sup>2</sup>/s. The values of specific capacity range between 1.03 × 10<sup>﹣1</sup> m<sup>2</sup>/s/m and 9.00 × 10<sup>﹣2</sup> m<sup>2</sup>/s/m, and these values indicate that the aquifers in the area have low to moderate ground water potentials. The low yield range of between 0.45 l/s and 1.00 l/s recorded in the area shows the heterogeneous and anisotropy nature of the basement aquifer system in terms of groundwater discharge. On the average, the boreholes assessed have potentials to sustain local to regional supply provided the best drilling method and materials are used and well completion properly done. 展开更多
关键词 Pumping test Heterogeneous ANISOTROPY conductivity Discharge Sanga
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基于正交试验的泡沫混凝土导热性能和孔结构研究
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作者 李琳 王宇 +2 位作者 马玉莹 沈寒琪 罗江红 《硅酸盐通报》 CAS 北大核心 2024年第8期2888-2896,共9页
以硫铝酸盐水泥、粉煤灰为胶凝材料,采用正交试验法研究了发泡剂、减水剂、增稠剂对于泡沫混凝土导热性能的影响并确定最优组合。制备5组不同密度(300、400、500、700、900 kg/m^(3))泡沫混凝土,采用Photoshop图像处理软件对各组样品截... 以硫铝酸盐水泥、粉煤灰为胶凝材料,采用正交试验法研究了发泡剂、减水剂、增稠剂对于泡沫混凝土导热性能的影响并确定最优组合。制备5组不同密度(300、400、500、700、900 kg/m^(3))泡沫混凝土,采用Photoshop图像处理软件对各组样品截面图进行二值化处理,并利用Image-Pro Plus软件对孔隙率、圆度值和孔径分布等孔结构特性进行分析。结果表明,影响泡沫混凝土导热系数的各因素主次顺序为增稠剂、发泡剂、减水剂。泡沫混凝土的密度与孔隙率呈负相关,相关系数R^(2)为0.91;密度越大,圆度值为1的孔隙占比越大。不同密度等级泡沫混凝土的孔径分布近似服从对数正态分布,孔径主要集中于200μm,且大孔径比例随着密度的增大而逐渐降低。 展开更多
关键词 泡沫混凝土 外加剂 正交试验 导热性能 孔结构
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Cystic fibrosis transmembrane conductance regulator functional evaluations in a G542X+/-IVS8Tn:T7/9 patient with acute recurrent pancreatitis 被引量:2
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作者 Sara Caldrer Gabriella Bergamini +12 位作者 Angela Sandri Silvia Vercellone Luca Rodella Angelo Cerofolini Francesco Tomba Filippo Catalano Luca Frulloni Mario Buffelli Gloria Tridello Hugo de Jonge Baroukh Maurice Assael Claudio Sorio Paola Melotti 《World Journal of Clinical Cases》 SCIE 2019年第22期3757-3764,共8页
BACKGROUND Acute recurrent pancreatitis(ARP)is characterized by episodes of acute pancreatitis in an otherwise normal gland.When no cause of ARP is identifiable,the diagnosis of"idiopathic"ARP is given.Mutat... BACKGROUND Acute recurrent pancreatitis(ARP)is characterized by episodes of acute pancreatitis in an otherwise normal gland.When no cause of ARP is identifiable,the diagnosis of"idiopathic"ARP is given.Mutations in the cystic fibrosis transmembrane conductance regulator(CFTR)gene increase the risk of ARP by 3-to 4-times compared to the general population,while cystic fibrosis(CF)patients present with a 40-to 80-times higher risk of developing pancreatitis.CASE SUMMARY In non-classical CF or CFTR-related disorders,CFTR functional tests can help to ensure a proper diagnosis.We applied an individualized combination of standardized and new CFTR functional bioassays for a patient referred to the Verona CF Center for evaluation after several episodes of acute pancreatitis.The CFTR genotype was G542X+/-with IVS8Tn:T7/9 polymorphism.The sweat(Cl-)values were borderline.Intestinal current measurements were performed according to the European Cystic Fibrosis Society Standardized Operating Procedure.Recent nasal surgery for deviated septum did not allow for nasal potential difference measurements.Lung function and sputum cultures were normal;azoospermia was excluded.Pancreas divisum was excluded by imaging but hypoplasia of the left hepatic lobe was detected.Innovative tests applied in this case include sweat rate measurement by image analysis,CFTR function in monocytes evaluated using a membrane potential-sensitive fluorescent probe,and the intestinal organoids forskolin-induced swelling assay.CONCLUSION Combination of innovative CFTR functional assays might support a controversial diagnosis when CFTR-related disorders and/or non-classical CF are suspected. 展开更多
关键词 Recurrent acute PANCREATITIS CYSTIC FIBROSIS CYSTIC FIBROSIS transmembraneconductance regulator function Intestinal current ORGANOIDS SWEAT test Controversialdiagnosis Case report
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基于电阻的冻结砂砾土孔隙冰压融效应研究
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作者 贾海梁 王亚彪 +4 位作者 魏尧 胡彬华 金龙 董元宏 唐丽云 《岩土力学》 EI CAS CSCD 北大核心 2024年第8期2221-2231,2241,共12页
为验证冻结砂砾土压缩过程中是否存在压融效应,对不同含水(冰)状态与不同冻结温度的砂砾土进行无侧限压缩试验和电阻测试,通过核磁共振测定饱和砂砾土的未冻水含量。结果表明:(1)砂砾土压缩过程电阻均先快速降低后趋缓,仅有干燥样品在... 为验证冻结砂砾土压缩过程中是否存在压融效应,对不同含水(冰)状态与不同冻结温度的砂砾土进行无侧限压缩试验和电阻测试,通过核磁共振测定饱和砂砾土的未冻水含量。结果表明:(1)砂砾土压缩过程电阻均先快速降低后趋缓,仅有干燥样品在应力峰值点后出现电阻增大的现象;(2)电阻快速降低阶段干燥样品的电阻降低率小于饱和冻结样品,−4℃饱和样品该值为26.8%,其值为相同温度下干燥样品的4倍;(3)随温度降低,电阻快速降低阶段的降低率先增加后减小;(4)随温度降低,自由水与毛细水的相对含量快速减小,吸附水的相对含量先小幅增加后缓慢降低。分析认为:冻结砂砾土压缩过程中存在压融效应,这导致样品在受荷过程中高应力区未冻水含量增大,而融水会沿未冻水膜向低应力区的孔隙迁移、复冰进而改变孔隙结构;冻结温度在−2~−4℃区间附近,压融效应更容易发生。 展开更多
关键词 冻结砂砾土 压融效应 无侧限压缩试验 电阻 导电路径
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基于单孔稀释试验的人工湖渗漏探测方法及应用
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作者 梁越 赵卓越 +2 位作者 夏日风 张宏杰 代磊 《人民长江》 北大核心 2024年第4期207-213,共7页
渗漏是影响湖库安全的关键因素,对其进行准确、高效探测一直是水工安全领域中的技术难题。与基于电磁理论的地球物理探测技术不同,基于井流理论的单孔稀释技术可以直接得到与渗流场相关的含水层参数且无需额外的参数转换。但传统的单孔... 渗漏是影响湖库安全的关键因素,对其进行准确、高效探测一直是水工安全领域中的技术难题。与基于电磁理论的地球物理探测技术不同,基于井流理论的单孔稀释技术可以直接得到与渗流场相关的含水层参数且无需额外的参数转换。但传统的单孔稀释试验往往仅对点位渗漏性进行定性判断,针对大尺度下渗漏规模的定量分析应用较少。为此,基于单孔稀释测速原理对四川省仁寿县某渗漏人工湖进行研究。在人工湖附近钻孔后进行单孔稀释试验,通过监测NaCl溶液电导率数据得到钻孔流速,通过解译流速数据得到了人工湖最大渗漏通道位于湖体左侧钻孔ZK6~ZK7区域420~440 cm深度范围和ZK8区域300~400 cm深度范围,钻孔剖面渗流量为4.24 cm^(3)/s。现场试验应用表明:单孔稀释法不仅能定性分析出渗漏通道的空间位置,还能定量计算出地下流速、渗流量参数。试验证明单孔稀释渗漏探测原理应用于湖库渗漏探测中具有较好的推广应用价值。 展开更多
关键词 渗漏探测 单孔稀释法 电导率 渗漏通道 渗漏量 人工湖
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双层地基中高导热能量桩热力学特性研究
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作者 常虹 吴琦琦 《吉林建筑大学学报》 CAS 2024年第3期52-56,共5页
通过室内模型试验,针对不同循环次数与桩顶荷载作用下高导热能量桩热力学特性进行研究。结果表明:桩身与土体温度随着循环次数增加存在累积行为,距离桩中轴线越远,土体温度越低,变化越小;桩身附加温度应力沿深度方向先减小后增大,最大... 通过室内模型试验,针对不同循环次数与桩顶荷载作用下高导热能量桩热力学特性进行研究。结果表明:桩身与土体温度随着循环次数增加存在累积行为,距离桩中轴线越远,土体温度越低,变化越小;桩身附加温度应力沿深度方向先减小后增大,最大附加温度应力位于-257 mm处,附加温度应力随着桩顶荷载和循环次数增加而增大;随着桩顶荷载增大,循环后桩顶沉降增大,桩顶沉降随着循环次数增加存在累积行为,在能量桩设计时予以充分考虑。 展开更多
关键词 高导热能量桩 模型试验 热力学特性 附加温度应力 桩顶位移
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基于相似模拟试验的顶板导水裂隙带高度及发育形态研究
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作者 张勃阳 张宇科 +2 位作者 黄虎威 林志斌 李亚超 《河南理工大学学报(自然科学版)》 CAS 北大核心 2024年第4期29-38,共10页
目的 为研究采动影响下顶板导水裂隙带高度及其发育形态,方法 以司马煤矿三采区1303工作面为研究对象,开展相似模拟试验,并以此为基础,对顶板的岩性组合加以改变,结合数字照相量测系统对不同岩性组合顶板导裂带高度和发育形态进行分析,... 目的 为研究采动影响下顶板导水裂隙带高度及其发育形态,方法 以司马煤矿三采区1303工作面为研究对象,开展相似模拟试验,并以此为基础,对顶板的岩性组合加以改变,结合数字照相量测系统对不同岩性组合顶板导裂带高度和发育形态进行分析,并进行理论验证。结果 结果表明:(1)工作面推进长度为160 m时,硬岩岩性顶板模型、硬-软岩岩性组合顶板模型以及软岩岩性顶板模型的导水裂隙带最大发育高度分别为69.6,55.6,61.1 m;(2)3种模型的导水裂隙带发育形态分别为底角50°的正梯形、前底角62°后底角60°的近似正梯形、前底角50°后底角60°的梯形;(3)根据模型试验和数据统计结果,给出适用于长治二岗山断褶带以南井田导水裂隙带发育高度预测式;(4)运用材料力学方法分析垮落角形成规律,垮落角与导水裂隙带发育高度呈反正切函数关系,并计算得到3种模型导水裂隙带前底角发育角度,分别为49.24°,61.21°和51.12°。通过导高计算公式得到3种模型导水裂隙带发育高度分别为74.1,51.1,59 m,均与相似模拟试验结果吻合。结论 研究结果对各类岩性顶板煤矿导水裂隙带发育高度预测具有参考意义。 展开更多
关键词 导水裂隙带 发育高度 发育形态 相似试验 顶板岩性组合
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测试条件对水流量平板法测试的热导率的影响
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作者 宋艳艳 王波 +2 位作者 王晓雨 李晓睿 张超 《耐火与石灰》 2024年第4期31-33,50,共4页
利用水流量平板法测试的热导率的公式确定了影响测试结果的试验参数,通过试验验证了中心量热器单位时间水流量和试样冷热面温差对热导率的影响。试验表明:在测试温度下试样的热导率随中心量热器单位时间水流量的增加而增大,但当中心量... 利用水流量平板法测试的热导率的公式确定了影响测试结果的试验参数,通过试验验证了中心量热器单位时间水流量和试样冷热面温差对热导率的影响。试验表明:在测试温度下试样的热导率随中心量热器单位时间水流量的增加而增大,但当中心量热器单位时间水流量超过一定值后,热导率增大趋势变缓;确定水流量平板法测试的热导率与试样冷热面温差有关,可通过热导率与Δt/ΔT的拟合曲线计算曲线范围内或曲线外推温度下的热导率。 展开更多
关键词 水流量平板法 热导率 冷热面温差 测试条件
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基于正交试验的免蒸压加气混凝土的制备与性能优化
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作者 刘小荟 彭晓彤 +2 位作者 汪洪伟 李维海 王鹏 《中国粉体技术》 CAS CSCD 2024年第6期74-84,共11页
【目的】制备轻质高强、节能保温的免蒸压加气混凝土,寻找最优制备配合比,提高固体废弃物的利用率。【方法】基于正交试验采用极差分析和矩阵关联分析的方法确定免蒸压加气混凝土的基础最优配比,优化玻璃粉的掺入量来实现加气混凝土性... 【目的】制备轻质高强、节能保温的免蒸压加气混凝土,寻找最优制备配合比,提高固体废弃物的利用率。【方法】基于正交试验采用极差分析和矩阵关联分析的方法确定免蒸压加气混凝土的基础最优配比,优化玻璃粉的掺入量来实现加气混凝土性能的提升。【结果】各因素对免蒸压加气混凝土的表观干密度和抗压强度的影响程度由大到小为铝粉掺量(质量分数,下同)、水泥掺量、水料比、聚丙烯纤维(PP纤维)掺量,加气混凝土的基础最优配比为水泥掺量为24%,水料比为0.44,铝粉掺量为0.13%,PP纤维掺量为0.4%;当玻璃粉质量替代率达到25%时,混凝土的综合性能达到最优。【结论】玻璃粉作为粉煤灰的替代材料,在改善免蒸压加气混凝土干密度、抗压强度、导热系数方面效果显著。 展开更多
关键词 免蒸压加气混凝土 玻璃粉 干密度 抗压强度 导热系数 正交试验
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有机肥料及其原料可溶性盐电导率测定方法的研究
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作者 赵英杰 刘少君 +6 位作者 李艳萍 李红凤 邢晓云 田有国 张世辉 汪洪 孟远夺 《肥料与健康》 CAS 2024年第2期64-69,共6页
为考察不同检测环境和条件对有机肥料及其生产原料的可溶性盐电导率(EC)测定结果的影响,选用不同类型的有机肥料及其生产原料开展了试验研究。结果表明:样品称样量与EC值测定结果呈线性正相关,对EC值的测定影响最大;样品浸提温度和浸提... 为考察不同检测环境和条件对有机肥料及其生产原料的可溶性盐电导率(EC)测定结果的影响,选用不同类型的有机肥料及其生产原料开展了试验研究。结果表明:样品称样量与EC值测定结果呈线性正相关,对EC值的测定影响最大;样品浸提温度和浸提液分离方法对EC值的测定无显著影响;振荡时间和样品浸提液放置时间对EC值的测定有显著影响,但处理间极差和相对极差较小。测定有机肥料及其生产原料EC值的条件:称样量为5.0~10.0 g,振荡时间为30~60 min,浸提液分离方式可根据实际情况选择滤纸过滤或离心分离,测定时的环境温度为25℃,样品浸提后静置30 min检测。 展开更多
关键词 有机肥料 生产原料 可溶性盐电导率 影响因素 测试分析
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