期刊文献+
共找到486篇文章
< 1 2 25 >
每页显示 20 50 100
基于Group-Res2Block的智能合成语音说话人确认方法
1
作者 李菲 苏兆品 +2 位作者 王年松 杨波 张国富 《应用科学学报》 CAS CSCD 北大核心 2024年第4期709-722,共14页
针对现有说话人确认任务基于自然语音条件下并不适用于智能合成语音的问题,提出一种基于Group-Res2Block的智能合成语音说话人确认方法。首先,设计了Group-Res2Block结构,在Res2Block的基础上将当前分组与相邻前后分组进行合并形成新的... 针对现有说话人确认任务基于自然语音条件下并不适用于智能合成语音的问题,提出一种基于Group-Res2Block的智能合成语音说话人确认方法。首先,设计了Group-Res2Block结构,在Res2Block的基础上将当前分组与相邻前后分组进行合并形成新的分组,以增强说话人局部特征的上下文联系;其次,设计了并行结构的多尺度通道注意力特征融合机制,利用不同大小卷积核实现同一层级的特征在通道维度的特征选择,以获取更具表现力的说话人特征,避免信息冗余;最后,设计了串行结构的多尺度层注意力特征融合机制,构建层结构,将深浅层特征整体进行融合并赋予不同权重,以获取最优的特征表达。为验证所提出特征提取网络的有效性,构建了中英文两种智能合成语音数据集进行消融实验和对比实验。结果表明本文方法在该任务的评价指标精确度(accuracy,ACC)、等错误率(equal error rate,EER)和最小检测代价函数(minimum detection cost function,minDCF)上是最优的。此外,通过对模型泛化性能进行测试,验证了本文方法对未知智能语音算法的适用性。 展开更多
关键词 说话人确认 智能合成语音 Group-Res2block深度神经网络 多尺度特征 注意力机制
下载PDF
Upregulation of α-ENaC induces pancreatic β-cell dysfunction,ER stress,and SIRT2 degradation
2
作者 Xue Zhang Dan Zhang +7 位作者 Lei Huo Xin Zhou Jia Zhang Min Li Dongming Su Peng Sun Fang Chen Xiubin Liang 《Journal of Biomedical Research》 CAS CSCD 2024年第3期241-255,共15页
Islet beta cells(β-cells)produce insulin in response to high blood glucose levels,which is essential for preserving glucose homeostasis.Voltage-gated ion channels inβ-cells,including Na+,K+,and Ca2+channels,aid in t... Islet beta cells(β-cells)produce insulin in response to high blood glucose levels,which is essential for preserving glucose homeostasis.Voltage-gated ion channels inβ-cells,including Na+,K+,and Ca2+channels,aid in the release of insulin.The epithelial sodium channel alpha subunit(α-ENaC),a voltage-independent sodium ion channel,is also expressed in human pancreatic endocrine cells.However,there is no reported study on the function of ENaC in theβ-cells.In the current study,we found thatα-ENaC was expressed in human pancreatic glandule and pancreatic isletβ-cells.In the pancreas of db/db mice and high-fat diet-induced mice,and in mouse isletβ-cells(MIN6 cells)treated with palmitate,α-ENaC expression was increased.Whenα-ENaC was overexpressed in MIN6 cells,insulin content and glucose-induced insulin secretion were significantly reduced.On the other hand,palmitate injured isletβ-cells and suppressed insulin synthesis and secretion,but increasedα-ENaC expression in MIN6 cells.However,α-ENaC knockout(Scnn1a−/−)in MIN6 cells attenuatedβ-cell disorder induced by palmitate.Furthermore,α-ENaC regulated the ubiquitylation and degradation of sirtuin 2 inβ-cells.α-ENaC also modulatedβ-cell function in correlation with the inositol-requiring enzyme 1 alpha/X-box binding protein 1(IRE1α/XBP1)and protein kinase RNA-like endoplasmic reticulum kinase/C/EBP homologous protein(PERK/CHOP)endoplasmic reticulum stress pathways.These results suggest thatα-ENaC may play a novel role in insulin synthesis and secretion in theβ-cells,and the upregulation ofα-ENaC promotes isletβ-cell dysfunction.In conclusion,α-ENaC may be a key regulator involved in isletβ-cell damage and a potential therapeutic target for type 2 diabetes mellitus. 展开更多
关键词 α-ENaC pancreaticβ-cells type 2 diabetes mellitus endoplasmic reticulum stress sirtuin 2
下载PDF
Databases of 2D material-substrate interfaces and 2D charged building blocks
3
作者 邓俊 潘金波 杜世萱 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期34-38,共5页
Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new mater... Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new materials in this respect.In van der Waals(vdW)layered materials,these building blocks are charge neutral and can be isolated from their bulk phase(top-down),but usually grow on substrate.In ionic layered materials,they are charged and usually cannot exist independently but can serve as motifs to construct new materials(bottom-up).In this paper,we introduce our recently constructed databases for 2D material-substrate interface(2DMSI),and 2D charged building blocks.For 2DMSI database,we systematically build a workflow to predict appropriate substrates and their geometries at substrates,and construct the 2DMSI database.For the 2D charged building block database,1208 entries from bulk material database are identified.Information of crystal structure,valence state,source,dimension and so on is provided for each entry with a json format.We also show its application in designing and searching for new functional layered materials.The 2DMSI database,building block database,and designed layered materials are available in Science Data Bank at https://doi.org/10.57760/sciencedb.j00113.00188. 展开更多
关键词 2D material-substrate interfaces charged building block database functional-oriented materials design layered materials density functional theory
下载PDF
The Effect of Tuberculosis Infection on Pancreatic Beta-Cell Function in Patients with Type 2 Diabetes Mellitus
4
作者 Mengdan Kong Ailin Zhong +1 位作者 Shilin Qu Junli Xue 《Advances in Bioscience and Biotechnology》 CAS 2024年第2期129-139,共11页
Objective: The aim of this study is to investigate how individuals with type 2 diabetes mellitus’ pancreatic β-cell function index and insulin resistance index are affected by tuberculosis infection. Methods: The st... Objective: The aim of this study is to investigate how individuals with type 2 diabetes mellitus’ pancreatic β-cell function index and insulin resistance index are affected by tuberculosis infection. Methods: The study group consisted of 89 patients with type 2 diabetes mellitus and tuberculosis infection who were admitted to Jingzhou Chest Hospital between March 2019 and March 2021. Gender and duration of diabetes were matching conditions. The control group was made up of 89 patients with type 2 diabetes who were admitted to Jingzhou Central Hospital’s endocrinology department during the same period. The two patient groups provided general information such as gender, age, length of diabetes, and blood biochemical indexes such as glycosylated hemoglobin (HbA1c), fasting glucose (FPG), and fasting C-peptide (FC-P). The HOMA calculator was used to calculate the HOMA-β and the HOMA-IR, and intergroup comparisons and correlation analyses were carried out. Results: Regarding gender, age, disease duration, FC-P, and HbA1c, the differences between the two groups were not statistically significant (P > 0.05). However, BMI, FPG, HOMA-β, and HOMA-IR showed statistically significant differences (P < 0.05). In comparison to the control group, the study group’s HOMA-β was lower and its HOMA-IR was greater. According to Spearman’s correlation analysis, HOMA-β had a negative association (P th FPG, HbA1c, and the length of the disease, and a positive correlation with BMI and FC-P. A positive correlation was found between HOMA-IR and BMI, FPG, and FC-P (P < 0.01), as well as a correlation with the length of the disease (P > 0.05) and HbA1c. Conclusions: In type 2 diabetes mellitus combined with tuberculosis infection, the patients had higher FPG levels and lower FC-P levels, the secretory function of pancreatic β-cells was more severely impaired, and insulin resistance was more obvious. 展开更多
关键词 Tuberculosis Infection Type 2 Diabetes Mellitus Pancreatic β-cell Function Insulin Resistance
下载PDF
苏北盆地江苏油田CO_(2)驱油技术进展及应用
5
作者 唐建东 王智林 葛政俊 《油气藏评价与开发》 CSCD 北大核心 2024年第1期18-25,F0002,共9页
CCUS(碳捕集、利用与封存)技术对绿色低碳转型、实现“双碳”目标意义重大,而CO_(2)驱油埋存是其重要内容。苏北盆地江苏油田针对复杂断块油藏提高采收率的技术瓶颈开展CO_(2)驱油技术攻关及多种类型矿场试验,形成了以重力稳定驱、驱吐... CCUS(碳捕集、利用与封存)技术对绿色低碳转型、实现“双碳”目标意义重大,而CO_(2)驱油埋存是其重要内容。苏北盆地江苏油田针对复杂断块油藏提高采收率的技术瓶颈开展CO_(2)驱油技术攻关及多种类型矿场试验,形成了以重力稳定驱、驱吐协同等为特点的复杂断块油藏CO_(2)驱油的4种差异化模式,成功开展了花26断块“仿水平井”重力稳定驱等技术先导试验,建成了10×10^(4) t的复杂断块油藏CCUS示范工程。江苏油田累计注入液碳量30.34×10^(4) t,累计增油量9.83×10^(4) t,实现了较好的增产效果及经济效益。技术研究及试验可为其他复杂断块油藏的CO_(2)驱开发提供参考借鉴。 展开更多
关键词 复杂断块 CO_(2)驱油模式 重力稳定驱 提高采收率 CO_(2)封存
下载PDF
Pancreaticβ-cell dysfunction in type 2 diabetes:Implications of inflammation and oxidative stress 被引量:2
6
作者 Phiwayinkosi V Dludla Sihle E Mabhida +6 位作者 Khanyisani Ziqubu Bongani B Nkambule Sithandiwe E Mazibuko-Mbeje Sidney Hanser Albert Kotze Basson Carmen Pheiffer Andre Pascal Kengne 《World Journal of Diabetes》 SCIE 2023年第3期130-146,共17页
Insulin resistance and pancreaticβ-cell dysfunction are major pathological mechanisms implicated in the development and progression of type 2 diabetes(T2D).Beyond the detrimental effects of insulin resistance,inflamm... Insulin resistance and pancreaticβ-cell dysfunction are major pathological mechanisms implicated in the development and progression of type 2 diabetes(T2D).Beyond the detrimental effects of insulin resistance,inflammation and oxidative stress have emerged as critical features of T2D that defineβ-cell dysfunction.Predominant markers of inflammation such as C-reactive protein,tumor necrosis factor alpha,and interleukin-1βare consistently associated withβ-cell failure in preclinical models and in people with T2D.Similarly,important markers of oxidative stress,such as increased reactive oxygen species and depleted intracellular antioxidants,are consistent with pancreaticβ-cell damage in conditions of T2D.Such effects illustrate a pathological relationship between an abnormal inflammatory response and generation of oxidative stress during the progression of T2D.The current review explores preclinical and clinical research on the pathological implications of inflammation and oxidative stress during the development ofβ-cell dysfunction in T2D.Moreover,important molecular mechanisms and relevant biomarkers involved in this process are discussed to divulge a pathological link between inflammation and oxidative stress duringβ-cell failure in T2D.Underpinning the clinical relevance of the review,a systematic analysis of evidence from randomized controlled trials is covered,on the potential therapeutic effects of some commonly used antidiabetic agents in modulating inflammatory makers to improveβ-cell function. 展开更多
关键词 Type 2 diabetes Insulin resistance β-cell dysfunction INFLAMMATION Oxidative stress
下载PDF
一类Block型李代数的2-局部导子
7
作者 肖明月 唐孝敏 《东北师大学报(自然科学版)》 CAS 北大核心 2023年第4期9-13,共5页
对一类Block型李代数的2-局部导子进行研究,证明了这类Block型李代数的2-局部导子都是导子.
关键词 block型李代数 导子 2-局部导子
下载PDF
准噶尔盆地东部北10井区中深层稠油CO_(2)非混相驱油技术 被引量:1
8
作者 许海鹏 张新奇 +3 位作者 刘蕊 夏近杰 王倩 董宏 《大庆石油地质与开发》 CAS 北大核心 2024年第1期142-148,共7页
准噶尔盆地东部北10井区头屯河组油藏具有埋藏深、原油黏度大、储层强水敏的特点,自探明以来一直未获得有效动用。为了解决油藏难动用的难题进行了CO_(2)-稠油实验,在实验结果的基础上,根据试验区生产现状提出“非混相驱+吞吐”措施,利... 准噶尔盆地东部北10井区头屯河组油藏具有埋藏深、原油黏度大、储层强水敏的特点,自探明以来一直未获得有效动用。为了解决油藏难动用的难题进行了CO_(2)-稠油实验,在实验结果的基础上,根据试验区生产现状提出“非混相驱+吞吐”措施,利用数值模拟手段优化生产参数得到最优方案并预测出生产指标。结果表明:地层稠油注入CO_(2)后原油体积膨胀和黏度降低的能力大幅增强,是提高采收率的主要机理;井区稠油CO_(2)驱替方式为非混相驱,驱替过程中CO_(2)先以溶解和扩散作用为主,待建立驱替通道后才开始产出原油,采收率为29.60%;试验区非混相驱初期见效慢,为加快受效提出“油井吞吐”措施,数值模拟预测非混相驱配合3轮油井吞吐生产,最终采收率可达21.0%,解决了研究区油藏难动用的难题。研究成果对中深层强水敏稠油油藏的动用具有一定的借鉴意义。 展开更多
关键词 中深层稠油 强水敏 CO_(2)非混相驱 提高采收率 北10井区
下载PDF
用于CO_(2)分离的Pebax基混合基质膜稳定性研究进展
9
作者 耿秀梅 张逢 +2 位作者 张翔 单美霞 张亚涛 《化工进展》 EI CAS CSCD 北大核心 2024年第9期4996-5012,共17页
膜技术在二氧化碳捕集和分离过程中以高效、节能、经济等优势成为当前研究的热潮。聚合物膜由于可加工性强、成本低廉等优点已被广泛商业化,但聚合物膜存在渗透性和选择性的“trade-off”效应问题,即高渗透性膜选择性反而低,反之亦然。... 膜技术在二氧化碳捕集和分离过程中以高效、节能、经济等优势成为当前研究的热潮。聚合物膜由于可加工性强、成本低廉等优点已被广泛商业化,但聚合物膜存在渗透性和选择性的“trade-off”效应问题,即高渗透性膜选择性反而低,反之亦然。将多孔材料加入聚合物基质中制备的混合基质膜能够实现气体渗透性和选择性的同时提升,成为气体分离膜领域的研究趋势。本文综述了聚醚嵌段聚酰胺(Pebax)为聚合物基质、多孔材料为填料所制备的混合基质膜在二氧化碳分离稳定性方面的研究进展。概述了沸石、金属有机骨架和共价有机骨架三类多孔材料在水、酸、碱和有机溶剂等存在下的化学稳定性并对其机理进行解释。重点介绍了以Pebax为基质的混合基质膜在CO_(2)分离过程中抗湿性和长期稳定性的研究现状。最后,针对膜稳定性在气体分离领域的发展,提出了多孔材料和膜在基础研究中的研究重点,指出了理论交叉实验以及多样化手段评估膜稳定性的研究方向。此外,从填料和聚合物的设计制备角度提出了改善膜稳定性的策略,旨在进一步提升Pebax混合基质膜对CO_(2)混合气体的分离稳定性。 展开更多
关键词 CO_(2)分离 多孔材料 聚醚嵌段聚酰胺(Pebax) 混合基质膜 稳定性
下载PDF
经方六君子汤加减对新发2型糖尿病伴脾气壅塞、痰瘀阻络型肥胖的干预作用 被引量:1
10
作者 张翠 裴琴 +2 位作者 潘慧 查敏 汪悦 《实用中医内科杂志》 2024年第3期67-71,共5页
目的 探讨经方六君子汤加减对新发2型糖尿病伴脾气壅塞、痰瘀阻络型肥胖患者的临床效果。方法 选择2023年1月-2023年9月南京市六合区中医院收治的60例新发2型糖尿病合并肥胖患者随机分为观察组和对照组各30例。对照组予德谷门冬双胰岛... 目的 探讨经方六君子汤加减对新发2型糖尿病伴脾气壅塞、痰瘀阻络型肥胖患者的临床效果。方法 选择2023年1月-2023年9月南京市六合区中医院收治的60例新发2型糖尿病合并肥胖患者随机分为观察组和对照组各30例。对照组予德谷门冬双胰岛素、盐酸二甲双胍治疗,观察组在对照组的基础上加用经方六君子汤加减治疗。比较两组治疗前后中医证候积分、腰围、体质量、身体质量指数(BMI)、空腹血糖(FBG)、餐后2 h血糖(2 hPBG)、糖化血红蛋白(HbA1c)、血脂四项(甘油三酯[TG]、总胆固醇[TC]、低密度脂蛋白[LDL]、高密度脂蛋白[HDL])、空腹胰岛素(FINS)、胰岛素抵抗指数(HOMA-IR)及不良反应。结果 治疗后,观察组总有效率明显高于对照组(P<0.05);两组中医证候积分、腰围、体质量、BMI、FBG、2 hPBG、HbA1c、TG、TC、LDL、HDL均明显改善(P<0.05),观察组均优于对照组(P<0.05)。治疗期间两组均出现低血糖1例,对照组腹泻1例,对症处理后好转,未出现明显血常规、肝肾功能异常。结论 新发2型糖尿病合并肥胖患者中加用经方六君子汤加减较单用德谷门冬双胰岛素联合盐酸二甲双胍片疗效更显著,可改善患者中医证侯积分、糖脂代谢相关指标等,不良反应少,效果满意。 展开更多
关键词 新发2型糖尿病 肥胖 经方六君子汤 脾气壅塞 痰瘀阻络
下载PDF
阳春沟区块页岩气超临界CO_(2)增能压裂研究与应用
11
作者 余前港 荣双 +4 位作者 毛国扬 崔连文 彭根博 向传刚 王旭 《石油与天然气化工》 CAS CSCD 北大核心 2024年第5期77-83,共7页
目的目前,超临界CO_(2)压裂应用前景广阔,为更好地指导现场应用,亟需明确超临界CO_(2)压裂的起裂压力和裂缝扩展规律。方法考虑压裂过程温度变化对CO_(2)物性的影响以及岩石中的热应力作用,建立热流固耦合超临界CO_(2)压裂模型。探究了... 目的目前,超临界CO_(2)压裂应用前景广阔,为更好地指导现场应用,亟需明确超临界CO_(2)压裂的起裂压力和裂缝扩展规律。方法考虑压裂过程温度变化对CO_(2)物性的影响以及岩石中的热应力作用,建立热流固耦合超临界CO_(2)压裂模型。探究了水平应力差、天然裂缝逼近角以及CO_(2)注入温度对裂缝起裂的影响。结果在阳春沟Y井开展的现场试验表明:与水力压裂相比,超临界CO_(2)压裂可以明显降低裂缝起裂压力,即使在高水平应力差下,仍可以获得复杂的裂缝形态;天然裂缝逼近角增大,起裂压力随之增大,裂缝复杂程度增加;CO_(2)注入温度与地层温差越大,热应力作用越明显,裂缝形态越复杂。结论现场应用显示注入前置超临界CO_(2)可以有效降低起裂压力,有利于提高后续水力压裂的缝内净压力,增强储层改造效果。 展开更多
关键词 超临界CO_(2)压裂 热流固多场耦合 热应力 相场模型 阳春沟区块
下载PDF
广义S-α_(2)型块对角占优矩阵及其谱分析
12
作者 朱开心 庹清 黄琦 《吉首大学学报(自然科学版)》 CAS 2024年第3期1-8,共8页
利用G-函数的性质和不等式的放缩技巧给出了一类块对角占优矩阵新的判定条件,以及对应矩阵的特征值包含域.数值算例说明了新判定条件的有效性和广泛性.
关键词 块H-矩阵 G-函数 特征值 广义S-α_(2)型块对角占优矩阵
下载PDF
Insufficient TRPM5 Mediates Lipotoxicity-induced Pancreaticβ-cell Dysfunction
13
作者 Kai-yuan WANG Shi-mei WU +2 位作者 Zheng-jian YAO Yun-xia ZHU Xiao HAN 《Current Medical Science》 SCIE CAS 2024年第2期346-354,共9页
Objective:While the reduction of transient receptor potential channel subfamily M member 5(TRPM5)has been reported in islet cells from type 2 diabetic(T2D)mouse models,its role in lipotoxicity-induced pancreaticβ-cel... Objective:While the reduction of transient receptor potential channel subfamily M member 5(TRPM5)has been reported in islet cells from type 2 diabetic(T2D)mouse models,its role in lipotoxicity-induced pancreaticβ-cell dysfunction remains unclear.This study aims to study its role.Methods:Pancreas slices were prepared from mice subjected to a high-fat-diet(HFD)at different time points,and TRPM5 expression in the pancreaticβcells was examined using immunofluorescence staining.Glucose-stimulated insulin secretion(GSIS)defects caused by lipotoxicity were mimicked by saturated fatty acid palmitate(Palm).Primary mouse islets and mouse insulinoma MIN6 cells were treated with Palm,and the TRPM5 expression was detected using qRT-PCR and Western blotting.Palm-induced GSIS defects were measured following siRNA-based Trpm5 knockdown.The detrimental effects of Palm on primary mouse islets were also assessed after overexpressing Trpm5 via an adenovirus-derived Trpm5(Ad-Trpm5).Results:HFD feeding decreased the mRNA levels and protein expression of TRPM5 in mouse pancreatic islets.Palm reduced TRPM5 protein expression in a time-and dose-dependent manner in MIN6 cells.Palm also inhibited TRPM5 expression in primary mouse islets.Knockdown of Trpm5 inhibited insulin secretion upon high glucose stimulation but had little effect on insulin biosynthesis.Overexpression of Trpm5 reversed Palm-induced GSIS defects and the production of functional maturation molecules unique toβcells.Conclusion:Our findings suggest that lipotoxicity inhibits TRPM5 expression in pancreaticβcells both in vivo and in vitro and,in turn,drivesβ-cell dysfunction. 展开更多
关键词 type 2 diabetes β-cell dysfunction LIPOTOXICITY TRPM5
下载PDF
Targeting neuronal PAS domain protein 2 and KN motif/ankyrin repeat domains 1:Advances in type 2 diabetes therapy
14
作者 Chun-Han Cheng Wen-Rui Hao Tzu-Hurng Cheng 《World Journal of Diabetes》 SCIE 2024年第11期2173-2176,共4页
This editorial summarizes the latest literature on the roles of neuronal PAS domain protein 2 and KN motif/ankyrin repeat domain 1 in type 2 diabetes(T2D).We highlight their involvement inβ-cell dysfunction,explore t... This editorial summarizes the latest literature on the roles of neuronal PAS domain protein 2 and KN motif/ankyrin repeat domain 1 in type 2 diabetes(T2D).We highlight their involvement inβ-cell dysfunction,explore their potential as therapeutic targets,and discuss the implications for new treatment strategies.We offer valuable insights into relevant gene regulation and cellular mechanisms relevant for the targeted management of T2D. 展开更多
关键词 Type 2 diabetes Neuronal PAS domain protein 2 KN motif and ankyrin repeat domain 1 β-cell dysfunction Therapeutic target
下载PDF
Influence of reservoir heterogeneity on immiscible water-alternating-CO_(2)flooding:A case study
15
作者 Peifeng Jia Chuanzhi Cui +1 位作者 Zhongwei Wu Dawei Yan 《Energy Geoscience》 EI 2024年第3期77-84,共8页
Currently,limited studies of immiscible water-alternating-CO_(2)(imWACO_(2))flooding focus on the impact of reservoir heterogeneity on reservoir development outcomes.Given this,using the heterogeneous reservoirs in th... Currently,limited studies of immiscible water-alternating-CO_(2)(imWACO_(2))flooding focus on the impact of reservoir heterogeneity on reservoir development outcomes.Given this,using the heterogeneous reservoirs in the Gao 89-1 block as a case study,this study conducted slab core flooding experiments and numerical simulations to assess the impact of reservoir heterogeneity on imWACO_(2)flooding efficiency.It can be concluded that imWACO_(2)flooding can enhance the sweep volume and oil recovery compared to continuous CO_(2)flooding.As the permeability difference increases,the difference in the swept volume between zones/layers with relatively high and low permeability increases.To optimize the exploitation of reservoirs in the Gao 89-1 block,the optimal timing and CO_(2)injection rate for imWACO_(2)flooding are determined at water cut of 40%and 10000 m^(3)/d,respectively.A short injection-production semi-period,combined with multiple cycles of water and CO_(2)injection alternations,is beneficial for enhanced oil recovery from imWACO_(2)flooding. 展开更多
关键词 Immiscible water-alternating-CO_(2)flooding Gao 89-1 block Slab experiment Numerical simulation Reservoir heterogeneity
下载PDF
CO_(2)对稠油油藏的物性调控及辅助蒸汽驱提高采收率
16
作者 魏鸿坤 王健 +3 位作者 许天寒 路宇豪 周娅芹 王俊衡 《新疆石油地质》 CAS CSCD 北大核心 2024年第2期221-227,共7页
为提高稠油油藏蒸汽驱后期开发效率,聚焦“双碳”背景下CCUS-EOR(碳捕集利用和封存体系提高采收率)技术的应用,以克拉玛依油田J6区为研究对象,通过对CO_(2)作用前后的稠油四组分分析,测试饱和压力、膨胀系数、黏度和密度变化情况,探究CO... 为提高稠油油藏蒸汽驱后期开发效率,聚焦“双碳”背景下CCUS-EOR(碳捕集利用和封存体系提高采收率)技术的应用,以克拉玛依油田J6区为研究对象,通过对CO_(2)作用前后的稠油四组分分析,测试饱和压力、膨胀系数、黏度和密度变化情况,探究CO_(2)对稠油物性的调控效果;通过并联岩心物理模拟实验研究CO_(2)辅助蒸汽驱提高采收率效果。研究结果表明:稠油黏度主要受胶质和沥青质含量影响,稠油随着CO_(2)溶解气量的增加,饱和压力由2.08 MPa上升至11.11 MPa,膨胀系数总体呈上升趋势,上升7.6%;同时,黏度降低30.5%,密度减小3.5%。表明CO_(2)在提高饱和压力的同时,通过优化膨胀系数、黏度和密度,有效改善了稠油物性。此外,采用CO_(2)辅助蒸汽驱后,在CO_(2)溶解降黏、破乳的作用下,稠油采收率从38.55%提高至46.46%,相比纯蒸汽驱提高了7.91%。为CO_(2)辅助蒸汽驱提高稠油采收率的应用提供了理论和实验基础,可为同类型稠油油藏提高采收率提供借鉴。 展开更多
关键词 克拉玛依油田J6区 稠油油藏 CO_(2) 蒸汽驱 提高采收率 物性调控 四组分分析 物理模拟
下载PDF
基于轻量化U^(2)-Net的车道线检测算法研究
17
作者 邓欢 王健 +3 位作者 吴孟军 杜若飞 费明哲 王云靖 《汽车工程师》 2024年第8期22-28,共7页
针对车道线遮挡、道路阴影等多车道驾驶环境下提取的车道线特征信息缺失造成预测车道线模糊、不连续等问题,提出一种基于轻量化U^(2)-Net的车道线检测算法。首先,以轻量化U^(2)-Net的残差U形模块(RSU)和多特征尺度融合获得全局信息丰富... 针对车道线遮挡、道路阴影等多车道驾驶环境下提取的车道线特征信息缺失造成预测车道线模糊、不连续等问题,提出一种基于轻量化U^(2)-Net的车道线检测算法。首先,以轻量化U^(2)-Net的残差U形模块(RSU)和多特征尺度融合获得全局信息丰富的车道线特征;其次,对车道线特征进行逐像素阈值判断,并选择最小二乘法结合感兴趣区域(ROI)中车道线簇进行车道线的拟合,实现多车道线检测并确认自车道线区域;最后,在图森(TuSimple)数据集上进行验证与分析。验证结果表明,所提出的车道线检测算法的平均准确率达到98.4%,相比于其他车道线检测网络,该算法的网络参数量较少,准确率较高。 展开更多
关键词 轻量化U^(2)-Net 残差U形模块 多车道线检测 自车道线
下载PDF
至多k个2连通块的图的最大边数
18
作者 刘艳芳 《闽南师范大学学报(自然科学版)》 2024年第1期115-120,共6页
对k=[√1.02n]和k=[√n],分别给出至多k个2连通块的n阶无等长圈图的最大边数g_(2)(n,k)的一个下界g_(2)(n,[√1.02n])≥n+√(2+899/2363)n(1-0(1)),g_(2)(n[√n])≥n+√(2+484/1279)n(1-0(1)),其中n为充分大的正整数.
关键词 圈长 边数 2连通块
下载PDF
急斜煤层EDZ围岩动态演化规律2D-BLOCK数值追踪模拟 被引量:4
19
作者 张立杰 柴鑫 +3 位作者 来兴平 蒋东晖 邹磊 胥海东 《西安科技大学学报》 CAS 北大核心 2008年第4期613-618,共6页
急斜特厚煤层高阶段综放开采中,开采扰动区(Excavation-Disturbed-Zone,EDZ)内顶煤及采空区围岩结构动态演化规律预计是安全开采的关键保障F技术之一。对苇湖梁煤矿+579E2EB1+2急倾斜煤层(64°)高阶段(52m)综放面开采中采空区顶板... 急斜特厚煤层高阶段综放开采中,开采扰动区(Excavation-Disturbed-Zone,EDZ)内顶煤及采空区围岩结构动态演化规律预计是安全开采的关键保障F技术之一。对苇湖梁煤矿+579E2EB1+2急倾斜煤层(64°)高阶段(52m)综放面开采中采空区顶板坍塌现象综合认识,采用2D-BLOCK精细数值模拟程序,建立了相应的离散元数值分析模型,进行动态数值追踪模拟计算,揭示了复杂环境下急斜厚煤层开采形成的采空区坍塌规律,为现场安全开采提供了科学依据。 展开更多
关键词 急斜煤层 开采扰动区 2D—block程序 数值追踪模拟 动态演化规律
下载PDF
Twin-Block矫治器在安氏Ⅱ类2分类错矫治中的应用研究 被引量:7
20
作者 张海余 张铁良 张石玮 《中国美容医学》 CAS 2010年第1期98-99,共2页
目的:分析探讨Twin-Block矫治器(双垫矫治器)在安氏II类2分类错矫治中的应用效果。方法:选择2007年2月~2008年8月来我院正畸科就诊的安氏II类2分类错并伴下颌后缩的患者9例,年龄8.5~11.5岁,根据矫治前侧位片颈椎形态判断为生长... 目的:分析探讨Twin-Block矫治器(双垫矫治器)在安氏II类2分类错矫治中的应用效果。方法:选择2007年2月~2008年8月来我院正畸科就诊的安氏II类2分类错并伴下颌后缩的患者9例,年龄8.5~11.5岁,根据矫治前侧位片颈椎形态判断为生长发育加速期或前期。重建咬合关系,制作Twin-Block矫治器,24h戴用矫治器,矫治后拍摄头颅侧位片,比较矫治前后的测量值并进行统计学分析。结果:在经过7~12个月的矫治后9例患者都取得了良好的疗效,磨牙尖牙均达到中性关系,治疗后面型明显改善。SNB角从75.6°增加至79.8°,平均增加4.2°(P<0.05);ANB角由6.5°减小到3.1°,平均减小3.4°(P<0.001);1/NA角平均增加15.5°(P<0.001);1/SN平均增加了17.8°(P<0.001);1/1平均减小了15.5°(P<0.05);MP/FH平均增加了3.0°(P<0.05)。结论:改良Twin-Block矫治器对安氏Ⅱ类2分类具有矫形作用,可诱导下颌功能性前移,协调上下颌关系,改善面型。 展开更多
关键词 TWIN-block矫治器 安氏Ⅱ类2分类错
下载PDF
上一页 1 2 25 下一页 到第
使用帮助 返回顶部