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基于Extra Trees模型的咪唑类离子液体植物毒性预测及SHAP值分析
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作者 茹雨璇 曹雨希西 +2 位作者 胡肖肖 邵云海 马琳 《宝鸡文理学院学报(自然科学版)》 2025年第3期17-22,44,共7页
目的构建一种高效可行的机器学习模型用于咪唑类离子液体对植物的毒性预测,为绿色、低毒性离子液体的开发提供理论支持和新思路。方法收集200余个咪唑类离子液体对植物的毒性实验数据集,基于SMILES字符串提取分子描述符,构建了一个Extra... 目的构建一种高效可行的机器学习模型用于咪唑类离子液体对植物的毒性预测,为绿色、低毒性离子液体的开发提供理论支持和新思路。方法收集200余个咪唑类离子液体对植物的毒性实验数据集,基于SMILES字符串提取分子描述符,构建了一个Extra Trees预测模型。模型的性能通过决定系数(R^(2))、均方根误差(RMSE)等指标进行评估,并采用SHapley Additive exPlanations(SHAP)值分析预测结果,以量化特征值对毒性预测的贡献程度。结果Extra Trees模型在测试集上显示出良好的预测性能(R^(2)=0.944,RMSE=0.351)。SHAP分析揭示了分子中非极性基团、支链/环状结构、分子量等物理化学性质及分子结构对植物毒性的影响。结论构建的Extra Trees模型能够快速准确地预测咪唑离子液体的植物毒性,具有较好的泛化能力和鲁棒性,可为环境风险评估及绿色离子液体的设计开发提供科学依据。 展开更多
关键词 咪唑离子液体 机器学习 extra Trees模型 植物毒性
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Evaluating serum extra spindle pole bodies-like 1 protein vs p53 antibody for hepatitis B virus-related hepatocellular carcinoma diagnosis
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作者 Yan-Fei Feng Hui-Kun Zhou +8 位作者 Bo-Bin Hu Hang Wang Heng-Kai Liang Lu Wei Qing-Mei Li Tu-Mei Su Qian-Bing Yin Ming-Hua Su Jian-Ning Jiang 《World Journal of Hepatology》 2025年第7期221-232,共12页
BACKGROUND Hepatitis B virus(HBV)infection is a leading cause of global hepatocellular carcinoma(HCC).Conventional biomarkers such as alpha-fetoprotein(AFP)demonstrate suboptimal sensitivity and specificity.Emerging e... BACKGROUND Hepatitis B virus(HBV)infection is a leading cause of global hepatocellular carcinoma(HCC).Conventional biomarkers such as alpha-fetoprotein(AFP)demonstrate suboptimal sensitivity and specificity.Emerging evidence suggests that serum extra spindle pole bodies like 1(ESPL1)protein and p53 antibody may improve diagnostic accuracy.AIM To assess and compare the diagnostic performance of serum ESPL1 protein and p53 antibody in HBV-related HCC(HBV-HCC).METHODS This case-control study from the First Affiliated Hospital of Guangxi Medical University enrolled 30 patients with chronic hepatitis B(CHB),30 with HBV-related liver cirrhosis(HBV-LC),55 with HBV-HCC,and 30 healthy controls.Serum ESPL1 protein and p53 antibody levels were quantified via ELISA.Diagnostic performance was evaluated using receiver operating characteristic(ROC)curve analysis,including sensitivity,specificity,and correlation with AFP.RESULTS Serum ESPL1 protein levels progressively increased across disease stages(CHB:89.9 ng/L;HBV-LC:188.83 ng/L;HBV-HCC:317.63 ng/L),with a significantly higher area under the ROC curve(AUC=0.917)than either p53 antibody(AUC=0.725)or AFP(AUC=0.678).p53 antibody levels were significantly elevated only in the HBVHCC group.ESPL1 demonstrated superior sensitivity and concordance with histopathological findings.A significant correlation between ESPL1 and p53 antibody levels was observed exclusively in the HBV-HCC group(r=0.320,P=0.017),suggesting potential interplay in malignant transformation.CONCLUSION Serum ESPL1 protein,a promising biomarker for early HBV-HCC detection,outperforms p53 antibody in diagnostic reliability.Higher ESPL1 levels correlate with increased HCC risk in chronic HBV patients. 展开更多
关键词 extra spindle pole bodies-like 1 p53 antibody Hepatocellular carcinoma Hepatitis B virus Diagnostic biomarker Case-control study
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Protective effects of oleic acid and polyphenols in extra virgin olive oil on cardiovascular diseases 被引量:1
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作者 Yan Lu Jun Zhao +6 位作者 Qiqi Xin Rong Yuan Yu Miao Manli Yang Hui Mo Keji Chen Weihong Cong 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期529-540,共12页
The Mediterranean diet has long been recognized as one of the most effective ways to prevent and improve cardiovascular disease.Extra virgin olive oil(EVOO)is the typical sources of fat in the Mediterranean diet which... The Mediterranean diet has long been recognized as one of the most effective ways to prevent and improve cardiovascular disease.Extra virgin olive oil(EVOO)is the typical sources of fat in the Mediterranean diet which have been shown to have noteworthy nutritional value and positive impact on human health.It is worth noting that EVOO owes its superior nutritional value to its bioactive composition.The main component of EVOO is monounsaturated fatty acids(MUFAs)in the form of oleic acid.Oleic acid accounts for up to 70%-80%of EVOO.Secondly,EVOO contains approximately more than 30 phenolic compounds,of which HT is essential for the protection against cardiovascular diseases.In this review,we focused on the potential mechanisms of oleic acid and polyphenols combat cardiovascular diseases risk in terms of oxidative stress,inflammation,blood pressure,endothelial function and cholesterol.This review might provide a reference for the studies on cardiovascular protective effects of EVOO. 展开更多
关键词 Cardiovascular diseases extra virgin olive oil Oleic acid POLYPHENOLS
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基于Extra Tree Classifier的水质安全建模预测
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作者 杨丽佳 陈新房 +1 位作者 赵晗清 汪世伟 《电脑与电信》 2024年第6期57-61,共5页
随着工业化和城市化的快速发展,水质安全问题日益受到关注。本研究利用一个包含7999条数据记录的水质分析数据集,涵盖多种化学物质浓度测量值与安全阈值,以及“是否安全”分类变量,运用Extr aTree Classifier模型进行水质安全建模预测... 随着工业化和城市化的快速发展,水质安全问题日益受到关注。本研究利用一个包含7999条数据记录的水质分析数据集,涵盖多种化学物质浓度测量值与安全阈值,以及“是否安全”分类变量,运用Extr aTree Classifier模型进行水质安全建模预测及数据分析。本研究目的在于提供一个可靠的模型,以帮助决策者和相关部门更好地监测和维护水质安全,从而保障公众健康和环境可持续发展。 展开更多
关键词 水质安全 Lazy Predict extra Tree Classifier k折交叉验证 机器学习
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Analysis of the Risk of Water Breakout in the Bottom Plate of High-Intensity Mining of Extra-Thick Coal Seams 被引量:1
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作者 Shuo Wang Hongdong Kang Xinchen Wang 《Journal of Geoscience and Environment Protection》 2024年第5期81-91,共11页
In order to clarify the danger of water breakout in the bottom plate of extra-thick coal seam mining, 2202 working face of a mine in the west is taken as the research object, and it is proposed to use the on-site moni... In order to clarify the danger of water breakout in the bottom plate of extra-thick coal seam mining, 2202 working face of a mine in the west is taken as the research object, and it is proposed to use the on-site monitoring means combining borehole peeping and microseismic monitoring, combined with the theoretical analysis to analyze the danger of water breakout in the bottom plate. The results show that: 1) the theoretically calculated maximum damage depth of the bottom plate is 27.5 m, and its layer is located above the Austrian ash aquifer, which has the danger of water breakout;2) the drill hole peeping at the bottom plate of the working face shows that the depth of the bottom plate fissure development reaches 26 m, and the integrity of the water barrier layer has been damaged, so there is the risk of water breakout;3) for the microseismic monitoring of the anomalous area, the bottom plate of the return air downstream channel occurs in the field with a one-week lag, which shows that microseismic monitoring events may reflect the water breakout of the underground. This shows that the microseismic monitoring events can reflect the changes of the underground flow field, which can provide a reference basis for the early warning of water breakout. The research results can provide reference for the prediction of sudden water hazard. 展开更多
关键词 extra-Thick Coal Seam High-Intensity Mining Microseismic Monitoring Water-Surge Hazard Borehole Peeping
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Clinical outcomes in patients diagnosed with extra-nodal Hodgkin lymphoma: a 20-year retrospective analysis of the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) database
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作者 Kingsley Nnawuba Anup Kumar Trikannad Ashwini Kumar +3 位作者 Sruthi Vellanki Tochukwu Nzeako Samantha Robinson Hanna Jensen 《Cancer Advances》 2024年第13期1-6,共6页
Background:Hodgkin lymphoma refers to a malignancy of the lymphatic tissue.Extra-nodal Hodgkin lymphoma(ENHL)is a rare variant consisting of Hodgkin lymphoma occurring outside the lymphatic system.Studies investigatin... Background:Hodgkin lymphoma refers to a malignancy of the lymphatic tissue.Extra-nodal Hodgkin lymphoma(ENHL)is a rare variant consisting of Hodgkin lymphoma occurring outside the lymphatic system.Studies investigating the epidemiology associated with ENHL are rare.Methods:618 ENHL cases were analyzed using the National Cancer Institute’s Surveillance,Epidemiology,and End Results(SEER)database(2000–2020).Demographics including sex,race/ethnicity,rural-urban continuum,age group(categorized as adolescent and young adult(AYA)if between years of 15 and 39,and adult if over the age of 40),and living status(alive/deceased)were examined,with survival status as the main outcome.Results:This study included 335 males(54.2%)and 283 females(45.8%).Of this total,47.9%were in the AYA group.In terms of ethnicity the distribution was 12.5%non-Hispanic Black,67.5%non-Hispanic White,5.2%non-Hispanic Asian/Pacific Islander,and 14.9%Hispanic.Bivariate analyses evidenced significant differences in survival by age group with 91.6%in AYA vs.72.4%in adults(P<0.001)alive by the end of the study period.Multivariable analyses identified age as a key predictor of survival,as the AYA patients had a lower odds ratio for death(odds ratio=0.25,P<0.001).In addition,survival outcomes were also impacted by race,with non-Hispanic Blacks showing higher survival probabilities.Regarding treatment,27.0%of patients underwent surgery,with 10.2%receiving post-surgery radiation,reducing odds of mortality(odds ratio=0.32,P=0.046).Conclusion:The background research as such,tends to affirm that these two factors–age and race are quite crucial in the prognosis as well as management of ENHL.Compared to adults,AYA patients had significantly lower odds of death,while non-Hispanic Black individuals exhibited reduced survival probabilities.It should be noted that 27.0%of patients underwent surgery with 10.2%receiving post-operative radiation which led to decrease in mortality rates.Thus,these results reiterate the necessity for tailor-made treatment methods according to demographic characteristics to boost patient outcomes effectively.For better ENHL care,future studies could shed light on these disparities and improve treatment regimens as needed. 展开更多
关键词 Hodgkin lymphoma extra nodal disease SEER cancer survival
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Extra-Axial Anaplastic Pleomorphic Xanthoastrocytoma Mimicking Meningioma: A Case Report with Literature Review
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作者 Kaoutar Stitou Ilias Zahir +5 位作者 Oualid Mohammed Hmamouche Marouane Hammoud Faycal Lakhdar Mohammed Benzagmout Khalid Chakour Mohammed El Faiz Chaoui 《Open Journal of Modern Neurosurgery》 2024年第3期203-211,共9页
Background: A number of meningeal neoplastic lesions may radiologically and clinically simulate meningioma, include hemangiopericytomas, solitary fibrous tumors, schwannomas, hematolymphoid lesions, metastases, and ot... Background: A number of meningeal neoplastic lesions may radiologically and clinically simulate meningioma, include hemangiopericytomas, solitary fibrous tumors, schwannomas, hematolymphoid lesions, metastases, and others very rarely, also may clinically mimic meningiomas. Case Description: We present the case of A 28-year-old male patient, with no notable medical history, who presented with worsening headaches for 3 months, imbalance, and visual deficits, An initial MRI revealed extra-axial lesion involving the right Parieto-occipital, The tumor was hypointense on T1-weighted MR images, hyperintense signals on T2-weightedMR images, and heterogeneously enhanced suggestive of a meningioma, total resection was achieved, and the histopathological analysis confirmed the diagnosis of an angioblastic meningioma. However, 15 months later, the patient presented with the same initial visual complaints. A subsequent MRI showed lesion recurrence, leading to a second surgical intervention. The histopathological analysis confirmed the diagnosis of an anaplastic xanthoastrocytoma. Conclusion: This represents an unusual location for an anaplastic pleomorphic xanthoastrocytoma, which should broaden the differential diagnosis of extra-axial lesions. 展开更多
关键词 Anaplastic Features BRAF extra-Axial High Mitotic Rate High Proliferation Index MENINGEAL Pleomorphic Xanthoastrocytoma
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Extra-corporeal membrane oxygenation in aortic surgery and dissection: A systematic review 被引量:1
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作者 Massimo Capoccia Marc O Maybauer 《World Journal of Critical Care Medicine》 2019年第8期135-147,共13页
BACKGROUND Very little is known about the role of extracorporeal membrane oxygenation(ECMO)for the management of patients undergoing major aortic surgery with particular reference to aortic dissection.AIM To review th... BACKGROUND Very little is known about the role of extracorporeal membrane oxygenation(ECMO)for the management of patients undergoing major aortic surgery with particular reference to aortic dissection.AIM To review the available literature to determine if there was any evidence.METHODS A systematic literature search through PubMed and EMBASE was undertaken according to specific key words.RESULTS The search resulted in 29 publications relevant to the subject:1 brief communication,1 surgical technique report,1 invited commentary,1 retrospective case review,1 observational study,4 retrospective reviews,13 case reports and 7 conference abstracts.A total of 194 patients were included in these publications of whom 77 survived.CONCLUSION Although there is no compelling evidence for or against the use of ECMO in major aortic surgery or dissection,it is enough to justify its use in this patient population despite current adverse attitude. 展开更多
关键词 Aortic dissection Aortic surgery extra-corporeal life support extracorporealmembrane oxygenation extracorporeal life support Mechanical circulatory support
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Vanadis 4 Extra模具钢的干滑动摩擦性能 被引量:5
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作者 张俊喜 陈百明 +3 位作者 易湘斌 郭小汝 梁泽芬 张振宇 《材料热处理学报》 EI CAS CSCD 北大核心 2017年第4期185-192,共8页
采用"销-盘"摩擦磨损试验测试不同滑动速度下Vanadis 4 Extra和Cr12MoV模具钢干滑动严重磨损的临界载荷,通过SEM、EDS、OM观察磨损形貌并分析磨损机理及原因。结果表明:滑动速度增大,两种钢严重磨损的临界载荷均减小,Vanadis ... 采用"销-盘"摩擦磨损试验测试不同滑动速度下Vanadis 4 Extra和Cr12MoV模具钢干滑动严重磨损的临界载荷,通过SEM、EDS、OM观察磨损形貌并分析磨损机理及原因。结果表明:滑动速度增大,两种钢严重磨损的临界载荷均减小,Vanadis 4Extra和Cr12MoV两种钢严重磨损的临界载荷分别为:0.691 m/s范围内为900 N和600 N;0.921 m/s时为700 N和300 N。载荷小于临界载荷时以磨粒磨损为主,大于临界载荷之后Vanadis 4 Extra以氧化磨损为主,Cr12MoV为氧化磨损和塑性变形。在不同滑动速度及载荷下,Vanadis 4 Extra模具钢的耐磨性均高于Cr12MoV钢3~18.3倍。 展开更多
关键词 Vanadis 4 extra 临界载荷 摩擦因数 磨损率
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Efficacy observation on herpes zoster treated by the comprehensive therapy of blocking, surrounding needling, pricking and cupping combined with bloodletting at Longyan(龙眼, Extra) acupoint 被引量:3
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作者 石跃 张喜鱼 +2 位作者 王建峰 赵紫昊 WANG Fang 《World Journal of Acupuncture-Moxibustion》 2013年第4期15-18,共4页
Objective To observe the analgesic effect on herpes zoster treated by the comprehensive therapy of blocking, surrounding needling, pricking and cupping combined with bloodletting at Longyan (龙眼, Extra) acupoint. M... Objective To observe the analgesic effect on herpes zoster treated by the comprehensive therapy of blocking, surrounding needling, pricking and cupping combined with bloodletting at Longyan (龙眼, Extra) acupoint. Methods According to the random mumber table, 104 cases of herpes zoster were randomized into an observation group and a control group, 52 cases in each one. In the observation group, the blocking method was used at the starting site and the ending site of herpetic zone, the surrounding needling method was applied toward the center of the painful zone, with horizontal needling technique; and the local pricking and cupping methods as well as the bloodletting at Longyan (Extra) acupoint were adopted. In the control group, Jiáj (夹脊 EX-B 2) at the corresponding affected nerve segments and the local Ashi points were selected and stimulated with electroacupuncture. The visual analogue scale (VAS) was adopted to determine the analgesic effect 20 min, 1, 6, 12, 24 and 48 h after treatment separately in each group. Results The onset time of analgesic effect in the observation group was shorter than that in the control group and the efficacy time of duration was longer than that in the control group (all P0.05). The analgesic effect and the result of comprehensive efficacy assessment were superior to those of the control group (both P0.05). Conclusion The comprehensive therapy of blocking, surrounding needling, pricking and cupping method combined with bloodletting at Longyan (Extra) achieves the significant analgesic effect on herpes zoster. 展开更多
关键词 herpes zoster BLOCKING surrounding needling pricking andcupping bloodletting Longyan (龙眼 extra acupoint analgesia
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Analysis on the Production Advantages of USA Pima Extra Long Staple Cotton
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作者 田立文 徐志武 +7 位作者 郑子漂 宁新民 崔建平 朱斌 徐海江 郭仁松 林涛 刘志清 《Agricultural Science & Technology》 CAS 2017年第5期892-903,共12页
This paper defines the following advantages of ELS (Extra Long Staple) also known as Pima cotton planted in the United States: first, the only variety which is concentrated in the planting area with good soil moist... This paper defines the following advantages of ELS (Extra Long Staple) also known as Pima cotton planted in the United States: first, the only variety which is concentrated in the planting area with good soil moisture and fertilizer retention performances and abundant light and heat resources; second; advanced and practi- cal material equipment and technology; third; high yield and good quality, significant planting scale benefit; fourth, feasible and reliable modernized intensive farm man- agement mode with large-scale agricultural machinery operation; fifth, high-efficient social services and policy support system, as well as reasonable planting layout, good brand influence, synchronization of high yield and good quality with large-scale benefits. Although the production capability of Pima cotton in the United States is considered to be the largest and most powerful country in the world, compared with the ELS production in China, both have their own advantages and characteristics. Therefore, it is suggested that by using the ELS production experience ol the Unit- ed Stages for reference, China should make use of the modern breeding technJques to accelerate the modification of synthetic genetic features of ELS variety, try its best to breed the ELS variety which is suitable for mechanical plucking as soon as possible, actively develop new technology to simplify the whole cost saving cultiva- tion, reform ELS production organization, vigorously develop the social service sys- tem, and adjust and optimize the ELS industry support policies, so as to fundamen- tally improve the competitiveness of China's ELS in international market. 展开更多
关键词 ELS extra Long Staple) or Pima cotton Natural Ecology Planting lay-out and scale Fiber quality Material equipment
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Confrontation between Quantized Periods of Some Extra-Solar Planetary Systems and Observations
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作者 A. B. Morcos 《International Journal of Astronomy and Astrophysics》 2013年第2期28-32,共5页
A simple formula, using the quantum numbers of solar system planets and some quantized extra-solar planets, to estimate the periods, is done. The quantum numbers, calculated by other authors, have been used to find th... A simple formula, using the quantum numbers of solar system planets and some quantized extra-solar planets, to estimate the periods, is done. The quantum numbers, calculated by other authors, have been used to find the orbital periods of solar system planets and some extra-solar planets. Observed periods have been used to compare them with the estimated periods from the given formula. It is found that the given relation is applicable perfectly for the solar system planets. Some extra-solar planets, of stars having approximately the same mass as the sun, are chosen to apply the same relation. The differences between the observed and calculated periods for the extra-solar systems have been calculated and tabulated. It is found that the percentage errors between the predicted values and the corresponding observed values for extra-planetary systems are controlled by the star’s mass and its quantum number. The percentage error decreases by increasing the quantum number, for quantum numbers over 4. When the quantum number is less than or equal 4, it is found that the percentage error decreases by decreasing the quantum number. 展开更多
关键词 Quantization PERIODS extra-Planetary extra-Solar PLANET
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利用Extra.FLV建设教学资源库
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作者 卞龙宝 《中国现代教育装备》 2010年第14期17-17,19,共2页
FLV是当前网络上最流行的视频格式,然而针对FLV格式文件进行剪辑、合并及转换等的操作并不是很方便。本文简单介绍了Extra.FLV软件在建设FLV格式视频教学资源库中的作用。
关键词 FLV视频教学extra.FLV资源库
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热处理对Vanadis 4 Extra模具钢组织与性能的影响 被引量:1
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作者 张俊喜 郭小汝 李晶 《化工机械》 CAS 2019年第4期386-389,404,共5页
研究了热处理工艺对Vanadis 4 Extra模具钢组织、硬度、冲击韧性和耐磨性的影响。结果表明:淬火处理后的显微组织为马氏体、残留奥氏体和碳化物;硬度随奥氏体化温度的升高先升后降,在1 020℃时硬度最高;残余奥氏体随奥氏体化温度的升高... 研究了热处理工艺对Vanadis 4 Extra模具钢组织、硬度、冲击韧性和耐磨性的影响。结果表明:淬火处理后的显微组织为马氏体、残留奥氏体和碳化物;硬度随奥氏体化温度的升高先升后降,在1 020℃时硬度最高;残余奥氏体随奥氏体化温度的升高而升高;随回火温度的升高,硬度和冲击韧性变化趋势相反,在500℃回火后,硬度达到最高值62.1HRC,而冲击韧性达到最低值50.1J/cm^2;磨损率随回火温度的升高先变化不大,但在600℃时急速增大。 展开更多
关键词 Vanadis 4 extra 热处理 冲击韧性 硬度 钢组织 耐磨性
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The Relationship between Fractures and Tectonic Stress Field in the Extra Low-Permeability Sandstone Reservoir at the South of Western Sichuan Depression 被引量:14
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作者 曾联波 漆家福 李跃纲 《Journal of China University of Geosciences》 SCIE CSCD 2007年第3期223-231,共9页
The formation and distribution of fractures are controlled by paleotectonic stress field, and their preservative status and effects on development are dominated by the modern stress field. Since Triassic, it has exper... The formation and distribution of fractures are controlled by paleotectonic stress field, and their preservative status and effects on development are dominated by the modern stress field. Since Triassic, it has experienced four tectonic movements and developed four sets of tectonic fractures in the extra low-permeability sandstone reservoir at the south of western Sichuan depression. The strikes of fractures are in the S-N, NE-SW, E-W, and NW-SE directions respectively. At the end of Triassic, under the horizontal compression tectonic stress field, for which the maximum principal stress direction was NW.SE, the fractures were well developed near the S-N faults and at the end of NE-SW faults, because of their stress concentration. At the end of Cretaceous, in the horizontal compression stress fields of the NE-SW direction, the stress was obviously lower near the NE-SW faults, thus, fractures mainly developed near the S-N faults. At the end of Neogene-Early Pleistocene, under the horizontal compression tectonic stress fields of E-W direction, stress concentrated near the NE-SW faults and fractures developed at these places, especially at the end of the NE-SE faults, the cross positions of NE-SW, and S-N faults. Therefore, fractures developed mostly near S-N faults and NE-SW faults. At the cross positions of the above two sets of faults, the degree of development of the fractures was the highest. Under the modern stress field of the NW-SE direction, the NW-SE fractures were mainly the seepage ones with tensional state, the best connectivity, the widest aperture, the highest permeability, and the minimum opening pressure. 展开更多
关键词 fracture tectonic stress field extra low-permeability reservoir south of western Sichuan depression
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On Restricted Connectivity and Extra Connectivity of Hypercubes and Folded Hypercubes 被引量:14
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作者 徐俊明 朱强 +1 位作者 侯新民 周涛 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第2期203-207,共5页
Given a graph G and a non-negative integer h, the h-restricted connectivity κh(G) of G is the minimum cardinality of a set of vertices of G, in which at least h neighbors of any vertex is not included, if any, whos... Given a graph G and a non-negative integer h, the h-restricted connectivity κh(G) of G is the minimum cardinality of a set of vertices of G, in which at least h neighbors of any vertex is not included, if any, whose deletion disconnects G and every remaining component has the minimum degree of vertex at least h; and the h-extra connectivity κh(G) of G is the minimum cardinality of a set of vertices of G, if any, whose deletion disconnects G and every remaining component has order more than h. This paper shows that for the hypercube Qn and the folded hypercube FQn, κ1(Qn)=κ(1)(Qn)=2n-2 for n≥3, κ2(Qn)=3n-5 for n≥4, κ1(FQn)=κ(1)(FQn)=2n for n≥4 and κ(2)(FQn)=4n-4 for n≥8. 展开更多
关键词 CONNECTIVITY conditional connectivity restricted connectivity extra connectivity HYPERCUBE folded hypercube
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STRESS FIELD ANALYSIS OF EXTRA-HEIGHT FORGING DIE USING FINITE ELEMENT METHOD 被引量:3
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作者 Xiaobo Liu Jianping Tan Youping Yi 《Journal of Central South University》 SCIE EI CAS 1999年第1期60-63,共4页
TheextraheightforgingdieinSouthewestAluminiumFabricationPlantisaspecialdieformakingarmamentandspecialcivilpr... TheextraheightforgingdieinSouthewestAluminiumFabricationPlantisaspecialdieformakingarmamentandspecialcivilproductsinChina.A... 展开更多
关键词 stress field analysis extra HEIGHT FORGING DIE FINITE ELEMENT method
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Mechanism and control technology of strong ground pressure behaviour induced by high-position hard roofs in extra-thick coal seam mining 被引量:12
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作者 Chao Pan Binwei Xia +2 位作者 Yujun Zuo Bin Yu Changnan Ou 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第3期499-511,共13页
This work aimed at revealing the mechanism of strong ground pressure behaviour(SGPB)induced by high-position hard roof(HHR).Based on the supporting structures model of HHR,a modified voussoir beam mechanical model for... This work aimed at revealing the mechanism of strong ground pressure behaviour(SGPB)induced by high-position hard roof(HHR).Based on the supporting structures model of HHR,a modified voussoir beam mechanical model for HHR was established by considering the gangue support coefficient,through which the modified expressions of limit breaking span and breaking energy of HHR were deduced.Combined with the relationship between the dynamic-static loading stress of supporting body(hydraulic support and coal wall)and its comprehensive supporting strength,the criteria of ground pressure behaviour(GPB)induced by HHR were discussed.The types of Ⅰ_(1),Ⅰ_(2),Ⅱ_(1),andⅡ_(2) of GPB were interpreted.Results showed that types Ⅰ_(1) and Ⅰ_(2) were the main forms of SGPB in extra-thick coal seam mining.The main manifestation of SGPB was static stress,which was mainly derived from the instability of HHR rather than fracture.Accordingly,an innovative control technology was proposed,which can weaken static load by vertical-well separated fracturing HHR.The research results have been successfully applied to the 8101 working face in Tashan coal mine,Shanxi Province,China.The results of a digital borehole camera observation and stress monitoring proved the rationality of the GPB criteria.The control technology was successful,paving the way for new possibilities to HHR control for safety mining. 展开更多
关键词 extra thick coal seam High-position hard roof Strong ground pressure behaviour Supporting structures Criteria of ground pressure behaviour Controlling effects
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Strain Limit of Extra Galvannealed Interstitial-Free and Bake Hardened Steel Sheets Under Different Stress Conditions 被引量:2
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作者 R Narayanasamy N L Parthasarathi +1 位作者 R Ravindran C Sathiya Narayanan 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2008年第5期56-60,共5页
The formability of bake hardened steel (thickness 0.82 mm), and the extra galvannealed IF steel (thickness 0.82 mm) have been studied. The suitability of the above steels for forming applications has been critical... The formability of bake hardened steel (thickness 0.82 mm), and the extra galvannealed IF steel (thickness 0.82 mm) have been studied. The suitability of the above steels for forming applications has been critically examined. The microstructure, tensile properties, and formability parameters of the above sheet metals were determined. The manufacturing process of the steels and the significance with reference to its formability were studied. 展开更多
关键词 bake hardened steel extra galvannealed IF steel microstructure forming limit diagram tensile parameter
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