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Indocyanine green clearance test and model for end-stage liver disease score of patients with liver cirrhosis 被引量:37
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作者 Sheng, Qin-Song Lang, Ren +3 位作者 He, Qiang Yang, Yong-Jiu Zhao, De-Fang Chen, Da-Zhi 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2009年第1期46-49,共4页
BACKGROUND: The indocyanine green (ICG) clearance test (clearance rate (K) and retention rate at 15 minutes (R(15))) is a sensitive indicator to evaluate liver function. The model for end-stage liver disease (MELD) sc... BACKGROUND: The indocyanine green (ICG) clearance test (clearance rate (K) and retention rate at 15 minutes (R(15))) is a sensitive indicator to evaluate liver function. The model for end-stage liver disease (MELD) score has emerged as a useful tool for estimating the mortality of patients awaiting liver transplantation and has recently been validated on patients with liver diseases of various etiologies and severity. In this study, we investigated the correlation between the ICG clearance test and MELD score of patients with liver cirrhosis. METHODS: From June 2007 to March 2008, 52 patients with liver cirrhosis admitted to our center were classified into Child-Pugh class A (8 patients), B (14) and C (30). The ICG clearance test (K value and R(15)) was performed by ICG pulse spectrophotometry (DDG-3300K), and the MELD scores of patients were calculated. RESULTS: As the Child-Pugh classification of liver function gradually deteriorated, the K value decreased, while R(15) and MELD score increased. There were significant statistical differences in K value, R(15) and MELD score in patients with different Child-Pugh classifications. Significant correlations were found between the parameters of the ICG clearance test (K value and R(15)) and MELD score. A negative correlation was observed between K value and MELD score (r=-0.892, P < 0.05), while a positive correlation was observed between R(15) and MELD score (r=0.804, P < 0.05). CONCLUSIONS: The ICG clearance test and MELD score are good parameters for evaluating liver function. Moreover, K value and R(15) have significant correlations with MELD score, especially the K value, which may be a convenient and appropriate indicator to evaluate liver function of patients with liver cirrhosis. 展开更多
关键词 liver function tests indocyanine green model for end-stage liver disease SPECTROPHOTOMETRY
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儿童心力衰竭诊断的研究进展
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作者 雷诗意(综述) 李晨阳 +2 位作者 刘玲娟 袁宇星 田杰(审校) 《中国当代儿科杂志》 北大核心 2025年第1期127-132,共6页
心力衰竭是一组复杂的临床综合征。儿童心力衰竭(pediatric heart failure,PHF)具有较高的病死率。早期诊断对于PHF的治疗和管理至关重要。在临床实践中,各种检验和检查在PHF的诊断中扮演着关键角色,包括不断更新的生物标志物、超声心... 心力衰竭是一组复杂的临床综合征。儿童心力衰竭(pediatric heart failure,PHF)具有较高的病死率。早期诊断对于PHF的治疗和管理至关重要。在临床实践中,各种检验和检查在PHF的诊断中扮演着关键角色,包括不断更新的生物标志物、超声心动图、心脏磁共振等。该文重点梳理PHF诊断的生物标志物、检查、联合检测及临床模型、分级及分期的相关研究,期望为PHF的诊断提供思路和方向。 展开更多
关键词 心力衰竭 诊断 生物标志物 联合检测 临床模型 分级与分期 儿童
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顺直型与弯曲型联合消能多级消力池水力特性研究
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作者 王一帆 杨磊 +1 位作者 向金虎 康亚亭 《中国农村水利水电》 北大核心 2025年第3期113-118,共6页
在地形地质等条件限制下,多级消力池往往由于水流衔接不畅导致下游的流态与消能效果较差。基于河北省青山水库溢流表孔及泄洪底孔消能防冲设计,采用数值模拟与模型试验相结合的方法,对一级消力池与二级消力池不同体型参数下池内特征水... 在地形地质等条件限制下,多级消力池往往由于水流衔接不畅导致下游的流态与消能效果较差。基于河北省青山水库溢流表孔及泄洪底孔消能防冲设计,采用数值模拟与模型试验相结合的方法,对一级消力池与二级消力池不同体型参数下池内特征水力参数的变化规律进行了研究。结果表明:当一级消力池池长满足稳定水跃发生条件后,继续增大池长对消能率的影响较小;尾坎高度(即池深)的降低导致收缩断面弗氏数逐渐增大,表孔侧与底孔侧一级消力池消能率随着坎高降低呈先增大再减小的变化规律;二级消力池直线段长度增大导致水跃位置下移,弯曲段轴线角度适度增大有利于提高消能率,但角度过大时消能率降低;在此基础上推荐了一级消力池与二级消力池联合消能的组合体型,并进行了数值模拟与模型试验研究。结果表明:延长一级池内的导墙可以显著改善二级池流态,各级消力池内跃前断面弗氏数均超过4.50,发生的水跃属于稳定水跃;综合消能率达到70.12%,较初设方案有明显提升。研究成果可为类似工程设计参考。 展开更多
关键词 多级消力池 联合消能 模型试验 数值模拟
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考虑压裂缝网连通的页岩气井组试井分析方法
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作者 胡小虎 刘华 +1 位作者 何辉 袁鸿飞 《油气藏评价与开发》 北大核心 2025年第1期79-87,共9页
针对页岩气藏邻井压裂、开发调整等引起的井间干扰等问题,现有基于单井或未考虑缝网连通的井组动态评价方法难以适用。基于变导流能力裂缝模型,构建了考虑压裂裂缝缝网连通的页岩气井组试井分析模型,对裂缝缝网进行离散化,将多级压裂井... 针对页岩气藏邻井压裂、开发调整等引起的井间干扰等问题,现有基于单井或未考虑缝网连通的井组动态评价方法难以适用。基于变导流能力裂缝模型,构建了考虑压裂裂缝缝网连通的页岩气井组试井分析模型,对裂缝缝网进行离散化,将多级压裂井井组模型方程转化为线性方程组进行求解并获得了井组井底压力解。通过有限体积数值方法对井组井底压力解进行了对比验证,建立了有连通裂缝和无连通裂缝时的井组井底压力典型曲线特征图,并给出了涪陵页岩气田2个平台4口井的应用实例。结果表明:①生产井具有双线性流1/4特征段、线性流1/2特征段、非稳态窜流特征段、边界拟稳态流特征段,而非生产井很难出现双线性和线性流特征段;②有连通裂缝和无连通裂缝情况下,利用有限体积数值方法计算的井组井底压力解与研究方法计算结果完全一致;③涪陵页岩气田2个平台4口井的实测数据解释评价结果与现场情况吻合,验证了方法的可靠性和实用性。研究成果可为页岩气藏储层参数的计算,压裂改造参数的计算以及井间连通性评价提供技术支持。 展开更多
关键词 页岩气 多级压裂 裂缝连通 井组 试井分析
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综合型立式泵用自动化测试金属夹具的研究与开发
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作者 王佳昱 刘同帮 +2 位作者 汪灿飞 平凡 戚胜坚 《世界有色金属》 2025年第2期227-229,共3页
金属夹具在有色金属行业中应用广泛,多用于固定有色金属工件,确保加工精度,例如在冲压和成型过程中固定材料,防止位移,还能根据特定需求设计,满足复杂形状或特殊工艺要求。本文题目中的综合型立式泵也广泛采用有色金属材质,例如铜合金... 金属夹具在有色金属行业中应用广泛,多用于固定有色金属工件,确保加工精度,例如在冲压和成型过程中固定材料,防止位移,还能根据特定需求设计,满足复杂形状或特殊工艺要求。本文题目中的综合型立式泵也广泛采用有色金属材质,例如铜合金材质的立式泵具备耐海水腐蚀、导热性好等特点。针对复杂多类型(为了解决不同进出口方向)立式多级泵同台快速测试的需要,我单位研制出一套自动化测试金属夹具系统,达到同台快速装夹泵产品的目的。从开发依据、结构原理设计、工作流程设计、参数设计4个方面,对该测试夹具进行非标设计。研制的真机在客户现场经实际运行检验,符合生产需求,有效提高了泵测试自动化程度。 展开更多
关键词 立式多级泵 非标自动化 测试夹具
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Dynamic properties and liquefaction behaviour of cohesive soil in northeast India under staged cyclic loading 被引量:2
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作者 Shiv Shankar Kumar A.Murali Krishna Arindam Dey 《Journal of Rock Mechanics and Geotechnical Engineering》 CSCD 2018年第5期958-967,共10页
Estimation of strain-dependent dynamic soil properties, e.g. the shear modulus and damping ratio, along with the liquefaction potential parameters, is extremely important for the assessment and analysis of almost all ... Estimation of strain-dependent dynamic soil properties, e.g. the shear modulus and damping ratio, along with the liquefaction potential parameters, is extremely important for the assessment and analysis of almost all geotechnical problems involving dynamic loading. This paper presents the dynamic properties and liquefaction behaviour of cohesive soil subjected to staged cyclic loading, which may be caused by main shocks of earthquakes preceded or followed by minor foreshocks or aftershocks, respectively. Cyclic triaxial tests were conducted on the specimens prepared at different dry densities (1.5 g/cm3 and 1.75 g/cm3) and different water contents ranging from 8% to 25%. The results indicated that the shear modulus reduction (G/Gmax) and damping ratio of the specimen remain unaffected due to the changes in the initial dry density and water content. Damping ratio is significantly affected by confining pressure, whereas G/Gmax is affected marginally. It was seen that the liquefaction criterion of cohesive soils based on single-amplitude shear strain (3.75% or the strain at which excess pore water pressure ratio becomes equal to 1, whichever is lower) depends on the initial state of soils and applied stresses. The dynamic model of the regional soil, obtained as an outcome of the cyclic triaxial tests, can be successfully used for ground response analysis of the region. 展开更多
关键词 Cohesive soil Dynamic soil properties Liquefaction potential Cyclic triaxial tests staged cyclic loading
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A Study on Physical Model Test for Cheongpyeong Dam Discharge Recalculation 被引量:1
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作者 Joongu Kang Sungjoong Kim Hongkoo Yeo 《Engineering(科研)》 2014年第11期731-742,共12页
Cheongpyeong Dam was built in 1943 for the purpose of power generation. Since its construction, discharge flow data based on a theoretical formula have been used to the present times and this leads to a problem of acc... Cheongpyeong Dam was built in 1943 for the purpose of power generation. Since its construction, discharge flow data based on a theoretical formula have been used to the present times and this leads to a problem of accurate discharge flow information not being available. In particular, Cheongpyeong Dam has been partially repaired and modified to maintain the dam structure over a long period of time and is not being properly reflected with changes at the downstream of the river caused by river improvement projects and sedimentation in reservoir. With a goal to improve Cheongpyeong Dam discharge flow calculation, this study aimed at verifying discharge capability and discharge flow by damper opening in relation to the previously suggested discharge flow through a hydraulic model test based on an accurate reproduction of the dam structure and surrounding topographies as in the present conditions. In this study, a hydraulic model test was conducted to examine the discharge flow of Cheongpyeong Dam. In addition, a comparative examination was carried out against the existing discharge flow proposed using theoretical equations. As a verification of the discharge flow of Cheongpyeong Dam, discharge flows in all sluices and a single sluice were examined. Then, the impact of sluice interference caused by the dam structure consisting with 24 sluices was investigated. As a result of the examination, it was found that the difference between discharge flow calculated using the existing theoretical equations and discharge flow derived from the hydraulic model test was insignificant. Based on the results of hydraulic model test, a formula to estimate stage-discharge flow at a sluice was derived and suggested. 展开更多
关键词 Cheongpyeong DAM HYDRAULIC Model test stage-DISCHARGE CURVE Recalculation
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Indocyanine green clearance test combined with MELD score in predicting the short-term prognosis of patients with acute liver failure 被引量:27
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作者 Hong-Ling Feng Qian Li +2 位作者 Lin Wang Gui-Yu Yuan Wu-Kui Cao 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2014年第3期271-275,共5页
BACKGROUND: Acute liver failure(ALF) is an acute severe deterioration of liver function with high mortality. Early and accurate prognostic assessment of patients with ALF is critically important. Although the model fo... BACKGROUND: Acute liver failure(ALF) is an acute severe deterioration of liver function with high mortality. Early and accurate prognostic assessment of patients with ALF is critically important. Although the model for end-stage liver disease(MELD) scores and King’s College Hospital(KCH) criteria are well-accepted as predictive tools, their accuracy is unsatisfactory.The indocyanine green(ICG) clearance test(ICGR15, ICG retention rate at the 15 minutes) is a sensitive indicator of liver function. In this study, we investigated the efficacy of the ICGR15 for the short-term prognosis in patients with ALF. We compared the predictive value of ICGR15 with the MELD scores and KCH criteria.METHODS: Sixty-nine patients who had been diagnosed with ALF were recruited retrospectively. ICGR15 had been performed by ICG pulse spectrophotometry and relevant clinical and laboratory indices were analyzed within 24 hours of diagnosis.In addition, the MELD scores and KCH criteria were calculated.RESULTS: The three-month mortality of all patients was 47.83%.Age, serum total bilirubin and creatinine concentrations,international normalized ratio for prothrombin time, ICGR15,MELD scores and KCH criteria differed significantly between surviving and deceased patients. A positive correlation was observed between ICGR15 and MELD scores(r=0.328, P=0.006).The ICGR15-MELD model, Logit(P)=0.096×ICGR15+0.174 ×MELD score–9.346, was constructed by logistic regression analysis. The area under the receiver operating characteristic curve was 0.855. When set the cut-off point to-0.4684, the sensitivity was 87.90% and specificity, 72.20%. The area under the receiver operating characteristic curve of the ICGR15-MELD model(0.855) was significantly higher than that of the ICGR15(0.793), MELD scores(0.776) and KCH criteria(0.659).Based on this cut-off value, the patients were divided into two groups. The mortality was 74.36% in the first group(ICGR15-MELD≥-0.4686) and 13.33% in the second group(ICGR15-MELD<-0.4686), with a significant difference between the two groups(χ2=25.307, P=0.000).CONCLUSION: The ICGR15-MELD model is superior to the ICGR15, MELD scores, and KCH criteria in predicting the shortterm prognosis of patients with ALF. 展开更多
关键词 acute liver failure indocyanine green clearance test model for end-stage liver disease PROGNOSIS
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Similar fecal immunochemical test results in screening and referral colorectal cancer
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作者 Sietze T van Turenhout Leo GM van Rossum +10 位作者 Frank A Oort Robert JF Laheij Anne F van Rijn Jochim S Terhaar sive Droste Paul Fockens René WM van der Hulst Anneke A Bouman Jan BMJ Jansen Gerrit A Meijer Evelien Dekker Chris JJ Mulder 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第38期5397-5403,共7页
AIM: To improve the interpretation of fecal immunochemical test (FIT) results in colorectal cancer (CRC) cases from screening and referral cohorts. METHODS: In this comparative observational study, two prospective coh... AIM: To improve the interpretation of fecal immunochemical test (FIT) results in colorectal cancer (CRC) cases from screening and referral cohorts. METHODS: In this comparative observational study, two prospective cohorts of CRC cases were compared. The first cohort was obtained from 10 322 average risk subjects invited for CRC screening with FIT, of which, only subjects with a positive FIT were referred for colonoscopy. The second cohort was obtained from 3637 subjects scheduled for elective colonoscopy with a positive FIT result. The same FIT and positivity threshold (OC sensor; ≥ 50 ng/mL) was used in both cohorts. Colonoscopy was performed in all referral subjects and in FIT positive screening subjects. All CRC cases were selected from both cohorts. Outcome measurements were mean FIT results and FIT scores per tissue tumor stage (T stage). RESULTS: One hundred and eighteen patients with CRC were included in the present study: 28 cases obtained from the screening cohort (64% male; mean age 65 years, SD 6.5) and 90 cases obtained from the referral cohort (58% male; mean age 69 years, SD 9.8). The mean FIT results found were higher in the referral cohort (829 ± 302 ng/mLvs 613 ± 368 ng/mL,P = 0.02). Tissue tumor stage (T stage) distribution was dif-ferent between both populations [screening population: 13 (46%) T1, eight (29%) T2, six (21%) T3, one (4%) T4 carcinoma; referral population: 12 (13%) T1, 22 (24%) T2, 52 (58%) T3, four (4%) T4 carcinoma], and higher T stage was significantly associated with higher FIT results (P < 0.001). Per tumor stage, no significant difference in mean FIT results was observed (screening vs referral: T1 498 ± 382 ng/mL vs 725 ± 374 ng/mL, P = 0.22; T2 787 ± 303 ng/mL vs 794 ± 341 ng/mL, P = 0.79; T3 563 ± 368 ng/mLvs 870 ± 258 ng/mL,P = 0.13; T4 not available). After correction for T stage in logistic regression analysis, no significant differences in mean FIT results were observed between both types of cohorts (P = 0.10). CONCLUSION: Differences in T stage distribution largely explain differences in FIT results between screening and referral cohorts. Therefore, FIT results should be reported according to T stage. 展开更多
关键词 Screening population Referral cohort Fecal immunochemical test Tumor stage distribution Colorectal cancer
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Testing Linearity of Nonparametric Component in Partially Linear Model 被引量:1
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作者 施三支 宋立新 《Northeastern Mathematical Journal》 CSCD 2007年第1期24-34,共11页
In this paper, we propose the test statistic to check whether the nonparametric function in partially linear models is linear or not. We estimate the nonparametric function in alternative by using the local linear met... In this paper, we propose the test statistic to check whether the nonparametric function in partially linear models is linear or not. We estimate the nonparametric function in alternative by using the local linear method, and then estimate the parameters by the two stage method. The test statistic under the null hypothesis is calculated, and it is shown to be asymptotically normal. 展开更多
关键词 partially linear model local linear estimation two stage method general likelihood ratio test
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STAGE在雷达系统显控软件测试中的应用
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作者 赵进科 杨贝松 王海明 《电子产品可靠性与环境试验》 2019年第A01期131-135,共5页
对雷达系统显控软件的测试方法进行了分析,针对航迹注入测试架构中存在的难题进行了深入的探讨,研究了一种基于STAGE软件的雷达系统显控软件的测试方法。该方法通过共享内存的方式实现STAGE与被测软件之间的数据交互,借助STAGE软件的图... 对雷达系统显控软件的测试方法进行了分析,针对航迹注入测试架构中存在的难题进行了深入的探讨,研究了一种基于STAGE软件的雷达系统显控软件的测试方法。该方法通过共享内存的方式实现STAGE与被测软件之间的数据交互,借助STAGE软件的图形用户界面功能,快速地设计测试场景,能够很大程度上提高被测软件测试的充分性,提升测试效率。 展开更多
关键词 養达系统 显控软件 软件测试 stage
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Wind Tunnel Test on the Wind-Resistant Behavior of a Long-Span Cable-Stayed Bridge during Erection
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作者 马存明 廖海黎 陶奇 《Journal of Southwest Jiaotong University(English Edition)》 2010年第2期112-117,共6页
In order to investigate the aerodynamic behavior of the Sutong bridge over Yangtze River during erection, a 1:50 sectional model of the bridge deck, a 1: 100 full aeroelastic model of the free standing pylon and a 1... In order to investigate the aerodynamic behavior of the Sutong bridge over Yangtze River during erection, a 1:50 sectional model of the bridge deck, a 1: 100 full aeroelastic model of the free standing pylon and a 1: 125 full aeroelastic model for the maxim cantilever configuration were built. The test results show that there was no serious vortex-induced vibration at the bridge deck, and that the free standing tower, the model scale and the turbulence intensity influenced static loading. The buffeting responses during the maximum cantilever configuration did not affect the safety of the bridge under construction. 展开更多
关键词 Cable-stayed bridge Erection stage Aerodynamic behavior Wind tunnel test
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基于K均值聚类算法和LSTM神经网络的管道腐蚀阶段预测方法 被引量:1
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作者 王新颖 刘岚 +2 位作者 陈海群 胡磊磊 谢逢豪 《腐蚀与防护》 CAS CSCD 北大核心 2024年第8期84-89,共6页
针对声发射检测获得的管道腐蚀信号,提出了一种基于K均值(K-means)聚类算法和长短期记忆(LSTM)神经网络的管道腐蚀阶段预测方法。首先,利用K-means聚类算法将腐蚀信号分类,再构建LSTM神经网络模型,并采取了无监督学习的方式,以声发射波... 针对声发射检测获得的管道腐蚀信号,提出了一种基于K均值(K-means)聚类算法和长短期记忆(LSTM)神经网络的管道腐蚀阶段预测方法。首先,利用K-means聚类算法将腐蚀信号分类,再构建LSTM神经网络模型,并采取了无监督学习的方式,以声发射波形为出发点,对模型进行参数优化,最后进行管道腐蚀阶段预测,并根据评价指标对模型进行评价。研究表明:对LSTM神经网络模型适当增加隐藏层,可以使得模型更加稳定,鲁棒性更好;与现有故障诊断模型相比,LSTM神经网络模型的精度更高。 展开更多
关键词 声发射无损检测 腐蚀阶段预测 K-MEANS聚类算法 长短期记忆(LSTM)神经网络 鲁棒性
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Testing Equality of Nonparametric Functions in Two Partially Linear Models
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作者 施三支 宋立新 杨华 《Northeastern Mathematical Journal》 CSCD 2008年第6期521-533,共13页
We propose the test statistic to check whether the nonpararnetric functions in two partially linear models are equality or not in this paper. We estimate the nonparametric function both in null hypothesis and the alte... We propose the test statistic to check whether the nonpararnetric functions in two partially linear models are equality or not in this paper. We estimate the nonparametric function both in null hypothesis and the alternative by the local linear method, where we ignore the parametric components, and then estimate the parameters by the two stage method. The test statistic is derived, and it is shown to be asymptotically normal under the null hypothesis. 展开更多
关键词 partially linear model local linear estimation two stage method general likelihood ratio test
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帕纳科X射线衍射仪开放式变温加热台的研制与应用
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作者 贺站锋 何云 《广东化工》 CAS 2024年第1期20-23,共4页
本研究根据科学研究工作的实际需求,成功研制了一套开放式变温加热台,可在不更换帕纳科X射线衍射仪附件的情况下,进行X射线衍射原位变温测试。通过对变温加热台进行峰位比对、温度校准以及实际样品的测试分析,结果表明:该开放式变温加... 本研究根据科学研究工作的实际需求,成功研制了一套开放式变温加热台,可在不更换帕纳科X射线衍射仪附件的情况下,进行X射线衍射原位变温测试。通过对变温加热台进行峰位比对、温度校准以及实际样品的测试分析,结果表明:该开放式变温加热台的测试结果准确可靠,稳定性好。此外,该加热台安装便捷,不仅提高了测试效率和科学服务水平,还节省了大额的购置费用. 展开更多
关键词 X射线衍射仪 加热台 变温测试 全岩测试 粘土测试
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双级时效工艺对QAl9-4铝青铜力学性能的影响 被引量:1
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作者 宗林 赵鸿金 +2 位作者 胡玉军 张兵 徐星星 《有色金属科学与工程》 CAS 北大核心 2024年第3期392-399,431,共9页
采用正交实验研究双级时效工艺对QAl9-4铝青铜组织与性能的影响。发现不同工艺参数对合金性能影响强度不同,影响顺序由大到小为二级时效温度>一级时效温度>一级时效时间>二级时效时间。对正交实验结果进行方差分析得到最优双... 采用正交实验研究双级时效工艺对QAl9-4铝青铜组织与性能的影响。发现不同工艺参数对合金性能影响强度不同,影响顺序由大到小为二级时效温度>一级时效温度>一级时效时间>二级时效时间。对正交实验结果进行方差分析得到最优双级时效工艺为(150℃/2h)+(500℃/2.5h),并以此工艺对合金进行处理。与单级时效处理相比,双级时效处理后的合金抗压强度、极限压缩率、硬度分别提升了14.79%、25.59%和5.28%。最后对不同时效工艺处理的合金进行显微结构表征,发现性能差异来源于双级时效处理后的合金含有更多弥散分布的强化相和更少的γ2相,因此对QAl9-4铝青铜进行双级时效处理可以获得比单级时效处理更优异的性能。 展开更多
关键词 铝青铜 抗压强度 双级时效 正交实验
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基于灰色关联分析的断层突水阶段化感知方法
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作者 孙文斌 张纪扬 +3 位作者 王晓 杨辉 樊建聪 ABDUMALIK Olimov 《中国安全科学学报》 CAS CSCD 北大核心 2024年第7期63-70,共8页
为提升煤矿断层水害感知水平,提出一种以断层活化演变机制和关键控制因素识别的断层突水阶段化感知方法,通过断层突水演化过程相似模拟试验研究工作面底板与断层破坏的演化特征,以底板破坏带应力、断层裂隙带应力、导水通道内水压等为... 为提升煤矿断层水害感知水平,提出一种以断层活化演变机制和关键控制因素识别的断层突水阶段化感知方法,通过断层突水演化过程相似模拟试验研究工作面底板与断层破坏的演化特征,以底板破坏带应力、断层裂隙带应力、导水通道内水压等为阶段监测参数,揭示各监测参数与涌水量变化的阶段特征;结合灰色关联性分析法,判定断层突水阶段转化的关键控制因素,进而根据断层突水分析与研究过程,提出断层突水阶段化感知方法。结果表明:底板破坏带、断层裂隙带的应力,导水通道内的水压等监测参数的数值变化特征在断层活化突水过程中呈现出明显的阶段特征,控制因素与涌水量的灰色关联度排序为:底板破坏带应力>断层裂隙带应力>导水通道水压,通过对关键控制因素的识别,可实现断层突水阶段的感知,揭示基于灰色关联分析的感知方法在原理上具备可行性。 展开更多
关键词 灰色关联性分析 断层突水 阶段化感知 关键控制因素 相似模拟试验
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Semi-Industrial Test of Underground Coal Gasification In Well No.2 in Xinhe, Xuzhou
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作者 杨兰和 《International Journal of Mining Science and Technology》 SCIE EI 1999年第2期172-175,共4页
The necessity of underground coal gasification is explained. The condition,technology character,and process of the semi-industrial test of underground coal gasification in well No. 2 at Xinhe, Xuzhou,are introduced. T... The necessity of underground coal gasification is explained. The condition,technology character,and process of the semi-industrial test of underground coal gasification in well No. 2 at Xinhe, Xuzhou,are introduced. The test results indicate that the technique of long tunnel,large sectiou,two stage underground coal gasification can obtain a large output of coal gas with a high heat value, making the working process stable. So the feasibility of the new techuology is verified. It can be concluded that there will have a good application prospect of the technique in China. 展开更多
关键词 UNDERGROUND COAL GASIFICATION semi-industrial test technology long tuunel large section two stage XUZHOU Xinhe
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基于正交试验的多级节流孔板流动特性分析
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作者 肖龙洲 甘润林 +3 位作者 蔡标华 俞健 胡洋 武哲 《船海工程》 北大核心 2024年第1期21-25,共5页
为降低多级节流孔板空化与湍流噪声,采用正交试验法分析多级节流孔板的孔分布、板厚、板间距等参数以及通流孔形状对空化和湍流噪声的影响,分析最小压力、湍流动能等流场参数的变化规律。通过极差分析得到各参数对流场性能影响的主次关... 为降低多级节流孔板空化与湍流噪声,采用正交试验法分析多级节流孔板的孔分布、板厚、板间距等参数以及通流孔形状对空化和湍流噪声的影响,分析最小压力、湍流动能等流场参数的变化规律。通过极差分析得到各参数对流场性能影响的主次关系,并筛选出空化与湍流噪声优化方案,结果表明,在满足通流能力的情况下,多级节流孔板孔的开孔形状对空化的影响较为显著;适当的增加孔板厚度与板间距,可以抑制空化的产生;同时增加多级节流孔板板间距和孔的分布间距,可以让流动更加平缓,减小湍流噪声。 展开更多
关键词 多级节流孔板 正交试验 空化 湍流噪声
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高速磁悬浮电机三段式转子动力学分析研究 被引量:2
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作者 李晖 徐向波 +1 位作者 陈劭 毕中炜 《微特电机》 2024年第3期6-10,共5页
为解决高速磁悬浮电机三段式转子的动力学分析问题,基于Workbench有限元仿真平台完成了三段式转子建模、模态振型计算、坎贝尔图求解、不平衡响应分析。总结讨论了关键因素对三段式转子的动力学特性的影响规律,并通过模态试验对转子建... 为解决高速磁悬浮电机三段式转子的动力学分析问题,基于Workbench有限元仿真平台完成了三段式转子建模、模态振型计算、坎贝尔图求解、不平衡响应分析。总结讨论了关键因素对三段式转子的动力学特性的影响规律,并通过模态试验对转子建模的合理性进行了验证。仿真结果与实验结果误差在5%,证明了建模及分析方法的可靠性,为应用在高速磁悬浮电机上同类转子的进一步优化设计和不平衡响应抑制提供理论参考。 展开更多
关键词 磁悬浮电机 三段式转子 临界转速 不平衡响应 模态试验
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