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Mathematical models of steady-state temperature fields produced by multi-piped freezing 被引量:8
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作者 Xiang-dong HU Wang GUO +2 位作者 Luo-yu ZHANG Jin-tai WANG Xue DONG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2016年第9期702-723,共22页
The multi-piped freezing method is usually applied in artificial ground freezing (AGF) projects to fulfill special construction requirements, such as two-, three-, or four-piped freezing. Based on potential superpos... The multi-piped freezing method is usually applied in artificial ground freezing (AGF) projects to fulfill special construction requirements, such as two-, three-, or four-piped freezing. Based on potential superposition theory, this paper gives analytical solutions to steady-state frozen temperature for two, three, and four freezing pipes with different temperatures and arranged at random. Specific solutions are derived for some particular arrangements, such as three freezing pipes in a linear arrangement with equal or unequal spacing, right and isosceles triangle arrangements, four freezing pipes in a linear arrangement with equal spacing, and rhombus and rectangle arrangements. A comparison between the analytical solutions and numerical thermal analysis shows that the analytical solutions are sufficiently precise. As a part of the theory of AGF, the analytical solutions of temperature fields for multi-piped freezing with arbitrary layouts and different temperatures of freezing pipes are approached for the first time. 展开更多
关键词 Artificial ground freezing (AGF) Multi-piped freezing Steady state Temperature field Analytical solution Potential function
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Correlation Structures between Satellite All-Sky Infrared Brightness Temperatures and the Atmospheric State at Storm Scales 被引量:1
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作者 Yunji ZHANG Eugene E.CLOTHIAUX David J.STENSRUD 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第5期714-732,共19页
This study explores the structures of the correlations between infrared(IR)brightness temperatures(BTs)from the three water vapor channels of the Advanced Baseline Imager(ABI)onboard the GOES-16 satellite and the atmo... This study explores the structures of the correlations between infrared(IR)brightness temperatures(BTs)from the three water vapor channels of the Advanced Baseline Imager(ABI)onboard the GOES-16 satellite and the atmospheric state.Ensemble-based data assimilation techniques such as the ensemble Kalman filter(EnKF)rely on correlations to propagate innovations of BTs to increments of model state variables.Because the three water vapor channels are sensitive to moisture in different layers of the troposphere,the heights of the strongest correlations between these channels and moisture in clear-sky regions are closely related to the peaks of their respective weighting functions.In cloudy regions,the strongest correlations appear at the cloud tops of deep clouds,and ice hydrometeors generally have stronger correlations with BT than liquid hydrometeors.The magnitudes of the correlations decrease from the peak value in a column with both vertical and horizontal distance.Just how the correlations decrease depend on both the cloud scenes and the cloud structures,as well as the model variables.Horizontal correlations between BTs and moisture,as well as hydrometeors,in fully cloudy regions decrease to almost 0 at about 30 km.The horizontal correlations with atmospheric state variables in clear-sky regions are broader,maintaining non-zero values out to~100 km.The results in this study provide information on the proper choice of cut-off radii in horizontal and vertical localization schemes for the assimilation of BTs.They also provide insights on the most efficient and effective use of the different water vapor channels. 展开更多
关键词 severe storm remote sensing data assimilation numerical modeling
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Correction to:Correlation Structures between Satellite All-Sky Infrared Brightness Temperatures and the Atmospheric State at Storm Scales 被引量:1
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作者 Yunji ZHANG Eugene E.CLOTHIAUX David J.STENSRUD 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第9期1588-1588,共1页
The article“Correlation Structures between Satellite All-Sky Infrared Brightness Temperatures and the Atmospheric State at Storm Scales”,written by Yunji ZHANG,Eugene E.CLOTHIAUX,and David J.STENSRUD was originally ... The article“Correlation Structures between Satellite All-Sky Infrared Brightness Temperatures and the Atmospheric State at Storm Scales”,written by Yunji ZHANG,Eugene E.CLOTHIAUX,and David J.STENSRUD was originally pub-lished electronically on the publisher’s internet portal on 30 of April 2021 without open access.With the author(s)’decision to opt for Open Choice,the copyright of the article changed on 26 of October 2021 to©The Author(s),2021 and the article is forthwith distributed under a Creative Commons Attribution 4.0 International License,which permits use,sharing,adapta-tion,distribution and reproduction in any medium or format,as long as you give appropriate credit to the original author(s)and the source,provide a link to the Creative Commons licence,and indicate if changes were made.The images or other third party material in this article are included in the article’s Creative Commons licence,unless indicated otherwise in a credit line to the material.If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use,you will need to obtain permission directly from the copyright holder.To view a copy of this licence,visit http://creativecommons.org/licenses/by/4.0.The original article has been corrected. 展开更多
关键词 STORM INFRARED otherwise
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An analysis of contributing mining factors in coal workers’pneumoconiosis prevalence in the United States coal mines,1986-2018 被引量:1
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作者 Younes Shekarian Elham Rahimi +2 位作者 Naser Shekarian Mohammad Rezaee Pedram Roghanchi 《International Journal of Coal Science & Technology》 EI CAS CSCD 2021年第6期1227-1237,共11页
In the United States,an unexpected and severe increase in coal miners’lung diseases in the late 1990s prompted researchers to investigate the causes of the disease resurgence.This study aims to scrutinize the effects... In the United States,an unexpected and severe increase in coal miners’lung diseases in the late 1990s prompted researchers to investigate the causes of the disease resurgence.This study aims to scrutinize the effects of various mining parameters,including coal rank,mine size,mine operation type,coal seam height,and geographical location on the prevalence of coal worker’s pneumoconiosis(CWP)in surface and underground coal mines.A comprehensive dataset was created using the U.S.Mine Safety and Health Administration(MSHA)Employment and Accident/Injury databases.The information was merged based on the mine ID by utilizing SQL data management software.A total number of 123,589 mine-year observations were included in the statistical analysis.Generalized Estimating Equation(GEE)model was used to conduct a statistical analysis on a total of 29,707,and 32,643 mine-year observations for underground and surface coal mines,respectively.The results of the econometrics approach revealed that coal workers in underground coal mines are at a greater risk of CWP comparing to those of surface coal operations.Furthermore,underground coal mines in the Appalachia and Interior regions are at a higher risk of CWP prevalence than the Western region.Surface coal mines in the Appalachian coal region are more likely to CWP development than miners in the Western region.The analysis also indicated that coal workers working in smaller mines are more vulnerable to CWP than those in large mine sizes.Furthermore,coal workers in thin-seam underground mine operations are more likely to develop CWP. 展开更多
关键词 Respirable coal mine dust Respiratory diseases Coal worker’s pneumoconiosis(CWP) Occupational exposure
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Future perspective of focal therapy for localized prostate cancer 被引量:1
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作者 Luke P.O’Connor Shayann Ramedani +4 位作者 Michael Daneshvar Arvin K.George Andre Luis Abreu Giovanni E.Cacciamani Amir H.Lebastchi 《Asian Journal of Urology》 CSCD 2021年第4期354-361,共8页
Objective:To summarize the recent literature discussing focal therapy for localized prostate cancer.Methods:A thorough literature review was performed using PubMed to identify recent studies involving focal therapy fo... Objective:To summarize the recent literature discussing focal therapy for localized prostate cancer.Methods:A thorough literature review was performed using PubMed to identify recent studies involving focal therapy for the treatment of localized prostate cancer.Results:In an effort to decrease the morbidity associated with prostate cancer treatment,many urologists are turning to focal therapy as an alternative treatment option.With this approach,the cancer bearing portion of the prostate is targeted while leaving the benign tissue untouched.Multiparametric magnetic resonance imaging remains the gold standard for visualization during focal therapy,but new imaging modalities such as prostate specific membrane antigen/positron emission tomography and contrast enhanced ultrasound are being investigated.Furthermore,several biomarkers,such as prostate cancer antigen 3 and prostate health index,are used in conjunction with imaging to improve risk stratification prior to focal therapy.Lastly,there are several novel technologies such as nanoparticles and transurethral devices that are under investigation for use in focal therapy.Conclusion:Focal therapy is proving to be a promising option for the treatment of localized prostate cancer.However,further study is needed to determine the true efficacy of these exciting new technologies. 展开更多
关键词 Focal therapy Prostate cancer Multiparametric magnetic resonance imaging IMAGING INNOVATION Technology
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The Two Cultures of Science: Implications for University-Industry Relationships in the U.S. Agriculture Biotechnology
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作者 William B Lacy Leland L Glenna +2 位作者 Dina Biscotti Rick Welsh Kate Clancy 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第2期455-466,共12页
Partnerships between U.S. universities and industries have existed for several decades and in recent years have become generally more varied, wider in scope, more aggressive and experimental and higher in public visib... Partnerships between U.S. universities and industries have existed for several decades and in recent years have become generally more varied, wider in scope, more aggressive and experimental and higher in public visibility. In addition, in the last few decades, public and private interests have advocated for government policies and laws to globally promote the commercialization of university science. This paper examines the persistence or convergence of the two cultures of science and the implications of this commercialization for university-industry relationships in agriculture biotechnology. The perceptions and values of over 200 U.S. university and industry scientists, managers and administrators who participate in or oversee research collaborations in agricultural biotechnology were analyzed. The findings revealed that the participants in these research relationships continue to perceive very distinct cultures of science and identify a wide range of concerns and disadvantages of these partnerships. Several actions were discussed to ensure that the two cultures serve complementary roles and that they maximize the public benefits from these increasing collaborations. 展开更多
关键词 two cultures of science agricultural biotechnology university-industry relationships
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Using yttrium as an indicator to estimate total rare earth element concentration:a case study of anthracite-associated clays from northeastern Pennsylvania
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作者 Xiaojing Yang Daniel Kozar +6 位作者 Daniel Gorski Anthony Marchese James Pagnotti Rusty Sutterlin Mohammad Rezaee Mark S.Klima Sarma V.Pisupati 《International Journal of Coal Science & Technology》 EI CAS 2020年第4期652-661,共10页
This study demonstrated using yttrium(Y)as an indicator to estimate the total rare earth element and Y contents(REY)in coal-associated samples and to facilitate selection of samples with high REY assays in a fast and ... This study demonstrated using yttrium(Y)as an indicator to estimate the total rare earth element and Y contents(REY)in coal-associated samples and to facilitate selection of samples with high REY assays in a fast and inexpensive manner.More than 10 anthracite-associated samples were collected from each of three Pennsylvanian sites(sites B,J and C)based on Thorium gamma ray logging suggesting high REY content.Several samples from each site were analyzed by ICP-MS to determine the rare earth distribution patterns and to establish the site-specific linear equations of Y and REY.The Y contents of the remaining samples were measured by a portable X-ray fluorescence analyzer,and the REY values were estimated based on the site-specific linear equation developed earlier.R-squared values above 0.70 were obtained for all the estimation equations from all three sites on both a whole sample basis and an ash basis.Previously,ash content has been widely used as an indicator of high REY content.This may not be applicable for a specific site.Site B in this study is an example where ash contents could not be statistically correlated with REY,so using Y for estimation is more applicable.The demonstrated sample screening process is suitable for samples from sites that share more similar distribution patterns(either MREY or LREY or HREY)as well as for samples from sites that share multiple distribution patterns(LREY/MREY/HREY)depending on the desirable accuracy.The demonstrated process lowers the analytical cost from$70 to 80 dollars per sample to$10-15 per sample while significantly reducing the processing time and acid consumption for ICP digestion.This is particularly true when a relatively large sample size is involved,for example,100 samples from one site analyzed by ICP-MS/OES. 展开更多
关键词 Rare earth elements XRF analysis CORRELATIONS Prediction ICP analysis
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洁净煤地质内涵、现状与未来发展方向 被引量:7
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作者 唐跃刚 王绍清 +4 位作者 王晓帅 郭鑫 王亚丰 薛李苹 Harold H.Schobert 《煤田地质与勘探》 北大核心 2025年第1期36-63,共28页
【目的】勘查与评价低碳、零排放和煤资源利用最大化是21世纪煤地质工作的重要内容。【研究进展】根据煤、煤地质学研究内容及洁净煤技术国内外发展趋势,定义了广义和狭义洁净煤地质学,其中,煤加工利用中提效减排的地质地球化学问题是... 【目的】勘查与评价低碳、零排放和煤资源利用最大化是21世纪煤地质工作的重要内容。【研究进展】根据煤、煤地质学研究内容及洁净煤技术国内外发展趋势,定义了广义和狭义洁净煤地质学,其中,煤加工利用中提效减排的地质地球化学问题是狭义煤地质学研究内容,煤炭勘探开发利用以及生态修复等全煤炭生命周期提效减排是广义洁净煤地质学研究内容。概述了煤中有益成分和有害成分的组成与分布,梳理了影响洁净煤技术的地质因素,主要与成煤作用过程中内生、外生地质作用相关,涉及构造、变质、火山喷发、岩浆侵入,风水搬运沉积,氧化还原,地下水等。详细综述了煤炭资源洁净评价、洁净加工、转化与利用等研究现状,回顾了中国洁净煤地质学的研究进展,归纳为萌芽-探索-成熟-确立-拓展等5个阶段。【问题与展望】提出了成煤作用、有机无机、矿物质和洁净评价等所存在的科学与技术问题;指出,未来化学、物理学、生物学及大数据人工智能等方面的发展为洁净煤地质学及其大型工程带来拓展机遇;未来十年,洁净煤时空分布、绿色智能煤气等共伴生矿产分质共采、洁净煤气化、煤基新材料、地下煤化工、生态修复等是重要研发方向,建议持续关注相关创新研究成果。 展开更多
关键词 洁净煤地质学 影响因素 加工利用 环境 研究现状 发展方向 中国
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Efficacy of Pelletized Lime versus Limestone Sand for Forest Regeneration Enhancement in Pennsylvania, USA
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作者 Nesha L. Mizel William E. Sharpe Bryan R. Swistock 《Open Journal of Forestry》 2015年第2期221-234,共14页
The efficacy of limestone sand and pelletized lime for remediation of soil acidity was compared in order to determine if limestone sand was a more cost-effective alternative to pelletized lime. Between fall of 2002 an... The efficacy of limestone sand and pelletized lime for remediation of soil acidity was compared in order to determine if limestone sand was a more cost-effective alternative to pelletized lime. Between fall of 2002 and spring 2003, two forested sites in Pennsylvania were clear cut and fenced. Pelletized lime and limestone sand were applied to separate 400-m2 plots within the sites at rates of 2170 kg·ha-1 and 4335 kg·ha-1, respectively. Two additional 400-m2 plots were used as controls. A paired before-after control-impact study design was used to assess changes in soil, soil solution, vegetation and biomass after lime application. Soil samples were collected from the Oi, Oe + Oa, and A horizons before and after lime application. Woody and herbaceous vegetation was harvested from 1-m2 sub-plots before and after liming and bi-weekly soil solution samples were collected for six months following lime application. Analysis of variance procedures were used to compare changes in the treatment plots over time. Changes in soil chemistry following lime application were comparable on the limestone sand and pelletized lime plots. There was a significant increase in exchangeable Mg and Mg saturation in the Oe + Oa horizon on all of the lime treatment plots relative to controls, but a greater percentage of applied Ca and Mg was exchangeable in the O-horizon in pelletized lime plots nine months after liming. Plant biomass did not increase on the lime treatment plots relative to the control one year post treatment. The majority of applied Ca and Mg from pelletized lime and limestone sand remained in the litter layer, with little movement into the A-horizon after one growing season. These results indicated that the application of limestone sand at two times the rate of pelletized lime produced comparable changes in soil and soil solution chemistry at a fraction of the cost. 展开更多
关键词 Forest REGENERATION Pelletized LIME LIMESTONE SAND SOIL SOIL Water
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Assessing the hazard of diesel particulate matter (DPM) in the mining industry: A review of the current state of knowledge
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作者 Sikandar Azam Shimin Liu +1 位作者 Sekhar Bhattacharyya Siyang Zheng 《International Journal of Coal Science & Technology》 CSCD 2024年第4期320-366,共47页
In the confined spaces of underground mines,the exposure of over 10,000 miners in the U.S.to diesel exhaust and diesel particulate matter(DPM)is an occupational inevitability,particularly in metal and nonmetal mineral... In the confined spaces of underground mines,the exposure of over 10,000 miners in the U.S.to diesel exhaust and diesel particulate matter(DPM)is an occupational inevitability,particularly in metal and nonmetal mineral extraction.These workers routinely operate amidst diesel-powered equipment,often outdated and highly polluting,extracting resources such as limestone,gold,and salt.The acute health effects of such exposure are significant,leading to symptoms like headaches and flu-like conditions,with the impact being more pronounced in these closed work environments.This review scrutinizes DPM's hazard in the mining sector,consolidating the extant knowledge and exploring ongoing research.It encapsulates our understanding of DPM's physicochemical properties,existing sampling methods,health ramifications,and mitigation technologies.Moreover,it underscores the necessity for further study in areas such as the evolution of DPM's physicochemical attributes,from its genesis at high-pressure,high-temperature conditions within diesel engines to its emission into the mine atmosphere.A key research gap is the intricate interaction of DPM with specific characteristics of the mine environment-such as relative humidity,ambient temperature,the presence of other mineral dust,and the dynamics of ventilation air.These factors can significantly alter the physicochemical profile of DPM,infuencing both its in-mine transport and its deposition behavior.Consequently,this can affect the respiratory health of miners,modifying the toxicity and the respiratory deposition of DPM particles.Identified research imperatives include(1)the advancement of instrumentation for accurate number measurement of DPM to replace or supplement traditional gravimetric methods;(2)the development of long-lasting,cost-effective control technologies tailored for the mining industry;(3)an in-depth investigation of DPM interactions within the unique mine microclimate,considering the critical components like humidity and other aerosols;and(4)understanding the differential impact of DPM in mining compared to other industries,informing the creation of mining-specific health and safety protocols.This review's findings underscore the urgency to enhance emission control and exposure prevention strategies,paving the way for a healthier underground mining work environment. 展开更多
关键词 Diesel particulate matter(DPM) Underground mine Environment Miner's health
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Vitamin d deficiency and metabolic syndrome:The joint effect on cardiovascular and all-cause mortality in the United States adults
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作者 Longjian Liu Saishi Cui +4 位作者 Stella L Volpe Nathalie S May Deeptha Sukumar Rose Ann DiMaria-Ghalili Howard J Eisen 《World Journal of Cardiology》 2022年第7期411-426,共16页
BACKGROUND The long-term impact of vitamin D deficiency and metabolic syndrome(MetS)on cardiovascular disease(CVD)and all-cause mortality are still a matter of debate.AIM To test the hypotheses that lower serum 25 hyd... BACKGROUND The long-term impact of vitamin D deficiency and metabolic syndrome(MetS)on cardiovascular disease(CVD)and all-cause mortality are still a matter of debate.AIM To test the hypotheses that lower serum 25 hydroxyvitamin D[25(OH)D]concentrations(a marker of vitamin D level)and MetS have a long-term impact on the risk of CVD and all-cause mortality,and individuals with vitamin D deficiency can be identified by multiple factors.METHODS A sample of 9094 adults,20 to 90 years of age,who participated in the Third National Health and Nutrition Examination Survey(NHANES III,1988 to 1994)were followed through December 2015 was analyzed.The associations of serum 25(OH)D concentrations and MetS with CVD and all-cause mortality were analyzed longitudinally using Cox regression models.Classification and regression tree(CART)for machine learning was applied to classify individuals with vitamin D deficiency.RESULTS Of 9094 participants,30%had serum 25(OH)D concentrations<20 ng/mL(defined as vitamin D deficiency),39%had serum 25(OH)D concentrations between 20 to 29 ng/mL(insufficiency),and 31%had serum 25(OH)D concentrations≥30 ng/mL(sufficiency).Prevalence of MetS was 28.4%.During a mean of 18 years follow-up,vitamin D deficiency and MetS were significantly associated with increased risk of CVD and all-cause mortality.Subjects with both vitamin D deficiency and MetS had the highest risk of CVD mortality(HR=1.77,95%CI:1.22-2.58)and all-cause mortality(HR=1.62,95%CI:1.26-2.09),followed by those with both vitamin D insufficiency and MetS for CVD mortality(HR=1.59,95%CI:1.12-2.24),and all-cause mortality(HR=1.41,95%CI:1.08-1.85).Meanwhile,vitamin D sufficiency significantly decreased the risk of CVD and all-cause mortality for those who even had MetS.Among the total study sample,CART analysis suggests that being non-Hispanic Black,having lower serum folate level,and being female were the first three predictors for those with serum 25(OH)D deficiency.CONCLUSION Vitamin D deficiency and MetS were significantly associated with increased risk of CVD and allcause mortality.There was a significant joint effect of vitamin D deficiency and MetS on the risk of mortality.Findings of the CART analysis may be useful to identify individuals positioned to benefit from interventions to reduce the risk of CVD and all-cause mortality. 展开更多
关键词 Joint effect Serum 25 hydroxyvitamin D concentration Metabolic syndrome Cardiovascular and all-cause mortality Cox model and machine learning
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Coulomb Interaction in H2 Molecule for States beyond the Ground State
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作者 Haiduke Sarafian 《Journal of Modern Physics》 2016年第6期528-535,共8页
The focus of our investigation is to evaluate one of the four contributing terms to the coulombic potential energy of an H<sub>2</sub> molecule. Specifically, we are interested in the term describing the e... The focus of our investigation is to evaluate one of the four contributing terms to the coulombic potential energy of an H<sub>2</sub> molecule. Specifically, we are interested in the term describing the electronic interaction of the charge distribution of one of the hydrogen atoms with the proton of the second atom. Quantum mechanics provides the charge distribution;hence, the evaluation of this term is a semi-classic quantum physics issue. For states other than the ground state the charge distributions are not spherically symmetric;they are functions of the radial and the angular coordinates. For the excited states we develop exact analytic expressions conducive to the potential energies. Because of the functional complexities of the wave functions, the evaluation of the core integrals is carried out utilizing symbolic capabilities of Mathematica [1]. Plots of these energies vs. the distance between the two protons reveal global features. 展开更多
关键词 Coulomb Potential Energy H2 Molecule Excited States of H2 Symbolic Calculation MATHEMATICA
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萃取改造对煤体多尺度孔隙结构与甲烷吸附动力学的影响机制
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作者 王亮 郑思文 付沈光 《煤炭学报》 北大核心 2025年第8期3933-3952,共20页
水力化技术作为煤层瓦斯治理的重要手段,常辅以有机化学抑制剂注入,通过抑制瓦斯的吸附行为来提升煤层瓦斯的抽采效率。为了探明有机试剂对煤体理化性质的改造作用及甲烷吸附动力学行为受到有机组分的影响机制,利用有机试剂二氯甲烷(DCM... 水力化技术作为煤层瓦斯治理的重要手段,常辅以有机化学抑制剂注入,通过抑制瓦斯的吸附行为来提升煤层瓦斯的抽采效率。为了探明有机试剂对煤体理化性质的改造作用及甲烷吸附动力学行为受到有机组分的影响机制,利用有机试剂二氯甲烷(DCM)、四氢呋喃(THF)、N,N-二甲基甲酰胺(DMF)和乙醇(EA)对试验煤样进行有机组分萃取和孔隙结构改造,综合采用傅里叶变换红外光谱(FT-IR)、场发射扫描电子显微镜(SEM-EDS)、拉曼光谱(Raman)、X射线光电子能谱(XPS)、^(13)C核磁共振(^(13)C-NMR)等表征手段和低压N_(2)、低温CO_(2)流体侵入法等孔隙分布测试手段对萃取改性前后的煤体物理及化学结构进行定性定量分析,探索基于微孔填充的积分优化模型的计算结果与萃取改造前后煤体对甲烷吸附的影响机制。结果表明:萃取改造作用导致高变质程度的无烟煤中有机组分发生不同程度变化,其中DMF的改造效果较强,其含氧官能团相对含量锐减,导致了煤的甲烷吸附能力降低(最大程度可从空白对照组的26.536 4 cm^(3)/g降至DMF处理后的10.983 0 cm^(3)/g);同时萃取改造作用改变了煤的孔隙结构,即中、大孔相对增加,微孔相对降低。通过优化微孔填充理论,解释了化学结构改变导致甲烷吸附量衰减作用机制;同时,利用分子模拟手段,通过径向配位分布函数定量对比了萃取改造下煤体限域效应强弱,获得了微孔填充与有机组分改变的内在关系,从微观化学角度解释了甲烷在煤体内部的吸附倾向。 展开更多
关键词 多尺度特征 有机质萃取 甲烷吸附 微孔填充 分子模拟
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Bcl-2抑制剂协同HDAC抑制剂通过PI3K/AKT/FoxO1轴抗急性T淋巴细胞白血病机制研究
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作者 宋丹丹 顾思雨 +1 位作者 宋春华 葛峥 《中国实验血液学杂志》 北大核心 2025年第6期1599-1608,共10页
目的:探索Bcl-2抑制剂维奈克拉(VEN)联合组蛋白去乙酰化酶(HDAC)抑制剂西达本胺(CDM)在急性T淋巴细胞白血病(T-ALL)中的协同抗白血病作用及其可能的作用机制。方法:CCK-8实验检测VEN、CDM单药及联合用药对T-ALL细胞系CEM和MOLT-4细胞增... 目的:探索Bcl-2抑制剂维奈克拉(VEN)联合组蛋白去乙酰化酶(HDAC)抑制剂西达本胺(CDM)在急性T淋巴细胞白血病(T-ALL)中的协同抗白血病作用及其可能的作用机制。方法:CCK-8实验检测VEN、CDM单药及联合用药对T-ALL细胞系CEM和MOLT-4细胞增殖的影响,流式细胞术检测VEN、CDM单药及联合用药对T-ALL细胞周期、细胞凋亡的影响,Western blot法检测细胞周期及凋亡相关蛋白的表达。通过网络药理学分析筛选VEN联合CDM在T-ALL中的关键作用通路,并在T-ALL细胞系、T-ALL患者原代细胞及公共数据库中进行验证。结果:VEN联合CDM具有协同抑制CEM和MOLT-4细胞增殖的作用。在细胞周期实验中,VEN联合CDM可诱导CEM和MOLT-4细胞G_(0)/G_(1)期阻滞,Western blot显示VEN联合CDM能显著下调cyclin E2和CDK2的表达,上调p21^(Waf1/Cip1)的表达。在细胞凋亡实验中,VEN联合CDM可显著诱导CEM和MOLT-4细胞凋亡,Western blot检测结果显示,VEN联合CDM通过下调Mcl-1、上调Bax和cleaved caspase-3促进细胞内源性凋亡。网络药理学分析筛选出10个关键节点基因,KEGG富集分析显示显著富集于cell cycle、PI3K-AKT信号通路及其下游FoxO信号通路。GO富集分析显示显著富集于G_(1)/S transition of mitotic cell cycle、cyclin-dependent protein kinase holoenzyme complex和kinase activity。Western blot显示VEN联合CDM在CEM和MOLT-4细胞中显著下调PI3K、AKT、p-AKT,上调FoxO1。FoxO1在T-ALL患者细胞中低表达,在GSE13159和GSE26713数据集中验证显示了同样的结果。结论:VEN联合CDM通过调控PI3K/AKT/FoxO1轴,抑制细胞增殖、诱导G_(0)/G_(1)期阻滞和促进细胞凋亡,发挥协同抗T-ALL作用。 展开更多
关键词 维奈克拉 西达本胺 急性T淋巴细胞白血病 FOXO1
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Particle transport in fractured geo-energy reservoirs considering the effect of fluid inertia and turbulent flow:A review 被引量:2
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作者 E.A.A.V.Edirisinghe M.S.A.Perera +2 位作者 D.Elsworth S.K.Matthai E.Goudeli 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1906-1939,共34页
Particle-fluid two-phase flows in rock fractures and fracture networks play a pivotal role in determining the efficiency and effectiveness of hydraulic fracturing operations,a vital component in unconventional oil and... Particle-fluid two-phase flows in rock fractures and fracture networks play a pivotal role in determining the efficiency and effectiveness of hydraulic fracturing operations,a vital component in unconventional oil and gas extraction.Central to this phenomenon is the transport of proppants,tiny solid particles injected into the fractures to prevent them from closing once the injection is stopped.However,effective transport and deposition of proppant is critical in keeping fracture pathways open,especially in lowpermeability reservoirs.This review explores,then quantifies,the important role of fluid inertia and turbulent flows in governing proppant transport.While traditional models predominantly assume and then characterise flow as laminar,this may not accurately capture the complexities inherent in realworld hydraulic fracturing and proppant emplacement.Recent investigations highlight the paramount importance of fluid inertia,especially at the high Reynolds numbers typically associated with fracturing operations.Fluid inertia,often overlooked,introduces crucial forces that influence particle settling velocities,particle-particle interactions,and the eventual deposition of proppants within fractures.With their inherent eddies and transient and chaotic nature,turbulent flows introduce additional complexities to proppant transport,crucially altering proppant settling velocities and dispersion patterns.The following comprehensive survey of experimental,numerical,and analytical studies elucidates controls on the intricate dynamics of proppant transport under fluid inertia and turbulence-towards providing a holistic understanding of the current state-of-the-art,guiding future research directions,and optimising hydraulic fracturing practices. 展开更多
关键词 Two-phase flows Rock fractures Proppant transport Fluid inertia Turbulent flows Hydraulic fracturing
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Pore-scale gas–water two-phase flow and relative permeability characteristics of disassociated hydrate reservoir 被引量:1
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作者 Yu-Xuan Xia Derek Elsworth +3 位作者 Sai Xu Xuan-Zhe Xia Jian-Chao Cai Cheng Lu 《Petroleum Science》 2025年第8期3344-3356,共13页
Clayey-silt natural gas hydrate reservoirs in the South China Sea exhibit loose and unconsolidated structures, heterogeneous pore structures, high clay mineral contents, and strong hydrophilicity. These characteristic... Clayey-silt natural gas hydrate reservoirs in the South China Sea exhibit loose and unconsolidated structures, heterogeneous pore structures, high clay mineral contents, and strong hydrophilicity. These characteristics complicate the gas-water two-phase flow process in porous media following hydrate decomposition, posing challenges for efficient development. This study examines the transport response of clayey-silt reservoir samples from the Shenhu area using gas-water two-phase flow experiments and CT scanning to explore changes in pore structure, gas-water distribution, and relative permeability under varying flow conditions. The results indicate that pore heterogeneity significantly influences flow characteristics. Gas preferentially displaces water in larger pores, forming fracture-like pores, which serve as preferential flow channels for gas migration. The preferential flow channels enhance gas-phase permeability up to 19 times that of the water phase when fluid pressures exceed total stresses. However,small pores retain liquid, leading to a high residual water saturation of 0.561. CT imaging reveals that these hydro-fractures improve gas permeability but also confine gas flow to specific channels. Pore network analysis shows that gas injection expands the pore-throat network, enhancing connectivity and forming fracture-like pores. Residual water remains trapped in smaller pores and throats, while structural changes, including new fractures, improve gas flow pathways and overall connectivity. Relative permeability curves demonstrate a narrow gas-water cocurrent-flow zone, a right-shifted iso-permeability point and high reservoir capillary pressure, indicating a strong "water-blocking" effect. The findings suggest that optimizing reservoir stimulation techniques to enhance fracture formation, reduce residual water saturation, and improve gas flow capacity is critical for efficient hydrate reservoir development. 展开更多
关键词 Clayey-silt reservoir Gasewater two-phase flow CT scanning Relative permeability Pore network model
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A Novel Method for Enhancing Oil Recovery by Thickened Supercritical CO_(2) Flooding in High-Water-Cut Mature Reservoirs 被引量:1
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作者 Kaoping Song Daigang Wang +3 位作者 Fengyuan Zhang Hong Fu Mingxing Bai Hamid Emami-Meybodi 《Engineering》 2025年第5期59-69,共11页
High-water-cut mature reservoirs typically serve as the“ballast”for ensuring China’s annual crude oil production of 200 million tons.Despite the use of water flooding and chemical methods,over 40%of crude oil remai... High-water-cut mature reservoirs typically serve as the“ballast”for ensuring China’s annual crude oil production of 200 million tons.Despite the use of water flooding and chemical methods,over 40%of crude oil remains unexploited.It is critical to develop efficient revolutionary technologies to further enhance oil recovery(EOR)by a large percentage in high-water-cut mature reservoirs.To address this issue,the potential of vertical remaining oil in Daqing Oilfield is first analyzed from massive monitoring data.Using molecular dynamics simulation to design optimal synthetic routine,a copolymer without flu-orine or silicon is synthesized by modifying vinyl acetate(VAc)with maleic anhydride(MA)and styrene(St),and treated as a supercritical CO_(2)(scCO_(2))thickener.The underlying EOR mechanism of the scCO_(2) thickener is thereafter clarified by high-temperature,high-pressure oil displacement experiments.The EOR effect by thickened scCO_(2) flooding in a typical high-water-cut mature reservoir is predicted,and future technological advancements of the technique are ultimately discussed.Results show that the ver-tical remaining oil enriched in weakly swept zones is a primary target for further EOR in high-water-cut mature reservoirs.The copolymer typically exhibits good solubility,strong dispersion stability,and high thickening effect in scCO_(2).Under an ambient pressure of 10 MPa and a temperature of 50℃,the disso-lution of copolymer at a mass concentration of 0.2%can effectively increase the viscosity of scCO_(2) by 39.4 times.Due to the synergistic effect between expanding vertical swept volume and inhibiting gas channel-ing,crude oil recovery can be further enhanced by 23.1%for a typical high-water-cut mature reservoir when the scCO_(2) viscosity is increased by 50 times.Our understandings demonstrate that the thickened scCO_(2) flooding technology has significant technical advantages in high-water-cut mature reservoirs,with challenges and future development directions in field-scale applications also highlighted. 展开更多
关键词 High-water-cut mature reservoirs Supercritical CO_(2)thickener Thickening effect Enhance oil recovery Inhibit gas channeling Expand swept volume
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Effects of probiotic treatment on the prognosis of patients with sepsis: a systematic review 被引量:2
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作者 Chao Gong Shengyong Xu +9 位作者 Youlong Pan Shigong Guo Joseph Harold Walline Xue Wang Xin Lu Shiyuan Yu Mubing Qin Huadong Zhu Yanxia Gao Yi Li 《World Journal of Emergency Medicine》 2025年第1期18-27,共10页
BACKGROUND: Sepsis, a common acute and critical disease, leads to 11 million deaths annually worldwide. Probiotics are living microorganisms that are beneficial to the host and may benefit sepsis outcomes, but their e... BACKGROUND: Sepsis, a common acute and critical disease, leads to 11 million deaths annually worldwide. Probiotics are living microorganisms that are beneficial to the host and may benefit sepsis outcomes, but their effects are stil inconclusive. This study aimed to evaluate the overal eff ect of probiotics on the prognosis of patients with sepsis.DATA RESOURCES: We searched several sources for published/presented studies, including Pub Med, EMBASE, Web of Science, the Cochrane Library and the US National Library of Medicine Clinical Trials Register(www.clinicaltrials.gov) updated through July 30, 2023, to identify all relevant randomized controlled trials(RCTs) or observational studies that assessed the effectiveness of probiotics or synbiotics in patients with sepsis and reported mortality. We focused primarily on mortality during the study period and analyzed secondary outcomes, including 28-day mortality, in-intensive care unit(ICU) mortality and other outcomes.RESULTS: Data from 405 patients in five RCTs and 108 patients in one cohort study were included in the analysis. The overall quality of the studies was satisfactory, but clinical heterogeneity existed. All adult studies reported a tendency for probiotics to reduce the mortality of patients with sepsis, and most studies reported a decreasing trend in the incidence of infectious complications, length of ICU stay and duration of antibiotic use. There was only one RCT involving children.CONCLUSION: Probiotics show promise for improving the prognosis of patients with sepsis, including reducing mortality and the incidence of infectious complications, particularly in adult patients. Despite the limited number of studies, especially in children, these findings will be encouraging for clinical practice in the treatment of sepsis and suggest that gut microbiota-targeted therapy may improve the prognosis of patients with sepsis. 展开更多
关键词 SEPSIS PROBIOTICS SYNBIOTICS MORTALITY Gut microbiota
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Water deficit affects the nitrogen nutrition index of winter wheat under controlled water conditions 被引量:1
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作者 Ben Zhao Anzhen Qin +7 位作者 Wei Feng Xinqiang Qiu Pingyan Wang Haixia Qin Yang Gao Guojie Wang Zhandong Liu Syed Tahir Ata-Ul-Karim 《Journal of Integrative Agriculture》 2025年第2期724-738,共15页
Nitrogen(N)uptake is regulated by water availability,and a water deficit can limit crop N responses by reducing N uptake and utilization.The complex and multifaceted interplay between water availability and the crop N... Nitrogen(N)uptake is regulated by water availability,and a water deficit can limit crop N responses by reducing N uptake and utilization.The complex and multifaceted interplay between water availability and the crop N response makes it difficult to predict and quantify the effect of water deficit on crop N status.The nitrogen nutrition index(NNI)has been widely used to accurately diagnose crop N status and to evaluate the effectiveness of N application.The decline of NNI under water-limiting conditions has been documented,although the underlying mechanism governing this decline is not fully understood.This study aimed to elucidate the reason for the decline of NNI under waterlimiting conditions and to provide insights into the accurate utilization of NNI for assessing crop N status under different water-N interaction treatments.Rainout shelter experiments were conducted over three growing seasons from 2018 to 2021 under different N(75 and 225 kg N ha^(-1),low N and high N)and water(120 to 510 mm,W0 to W3)co-limitation treatments.Plant N accumulation,shoot biomass(SB),plant N concentration(%N),soil nitrate-N content,actual evapotranspiration(ET_a),and yield were recorded at the stem elongation,booting,anthesis and grain filling stages.Compared to W0,W1 to W3 treatments exhibited NNI values that were greater by 10.2 to 20.5%,12.6to 24.8%,14 to 24.8%,and 16.8 to 24.8%at stem elongation,booting,anthesis,and grain filling,respectively,across the 2018-2021 seasons.This decline in NNI under water-limiting conditions stemmed from two main factors.First,reduced ET_(a) and SB led to a greater critical N concentration(%N_(c))under water-limiting conditions,which contributed to the decline in NNI primarily under high N conditions.Second,changes in plant%N played a more significant role under low N conditions.Plant N accumulation exhibited a positive allometric relationship with SB and a negative relationship with soil nitrate-N content under water-limiting conditions,indicating co-regulation by SB and the soil nitrate-N content.However,this regulation was influenced by water availability.Plant N accumulation sourced from the soil nitrate-N content reflects soil N availability.Greater soil water availability facilitated greater absorption of soil nitrate-N into the plants,leading to a positive correlation between plant N accumulation and ET_(a)across the different water-N interaction treatments.Therefore,considering the impact of soil water availability is crucial when assessing soil N availability under water-limiting conditions.The findings of this study provide valuable insights into the factors contributing to the decline in NNI among different water-N interaction treatments and can contribute to the more accurate utilization of NNI for assessing winter wheat N status. 展开更多
关键词 critical nitrogen concentration shoot biomass plant nitrogen accumulation soil nitrate N concentration soil water content
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Time-evolution of ScCO_(2)-weakened coal integrity:Chemo-hydromechanical coupling and geological sequestration implications 被引量:1
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作者 Peng Liu Jingtao Yang +4 位作者 Baisheng Nie Ang Liu Wei Zhao Hao Xu Hengyi He 《International Journal of Mining Science and Technology》 2025年第6期961-973,共13页
Geological sequestration of CO_(2)is critical for deep decarbonization,but the geomechanical stability of coal reservoirs remains a major challenge.This study integrates nanoindentation,XRD/SEM-EDS chemo physical char... Geological sequestration of CO_(2)is critical for deep decarbonization,but the geomechanical stability of coal reservoirs remains a major challenge.This study integrates nanoindentation,XRD/SEM-EDS chemo physical characterization and 4D CT visualization to investigate the time-evolving mechanical degradation of bituminous coals with ScCO_(2)injection.The main results show that 4 d of ScCO_(2)treatment caused 50.47%–80.99%increase in load–displacement deformation and 26.92%–76.17%increase in creep depth at peak load,accompanied by 55.01%–63.38%loss in elastic modulus and 52.83%–74.81%reduction in hardness.The degradation exhibited biphasic kinetics,characterized by rapid surface-driven weakening(0–2 d),followed by stabilized matrix-scale pore homogenization(2–4 d).ScCO_(2)preferentially dissolved carbonate minerals(dolomite),driving pore network expansion and interfacial debonding,while silicate minerals resisted dissolution but promoted structural homogenization.These coupled geochemical-mechanical processes reduced the mechanical heterogeneity of the coal and altered its failure modes.The results establish a predictive framework for reservoir stability assessment and provide actionable insights for optimizing CO_(2)enhanced coalbed methane recovery. 展开更多
关键词 CO_(2)sequestration NANOINDENTATION Reservoirs stability Coal mechanics
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