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Fracture propagation of deflagration fracturing in deep shale multi-branch wells
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作者 ZHU Haiyan WANG Enbo +6 位作者 TANG Kai YI Xiangyi ZHAO Peng LI Qin ZHU Jianqiao XU Dezhao DENG Ying 《Petroleum Exploration and Development》 2025年第4期1064-1073,共10页
Based on the finite element-discrete element numerical method,a numerical model of fracture propagation in deflagration fracturing was established by considering the impact of stress wave,quasi-static pressure of expl... Based on the finite element-discrete element numerical method,a numerical model of fracture propagation in deflagration fracturing was established by considering the impact of stress wave,quasi-static pressure of explosive gas,and reflection of stress wave.The model was validated against the results of physical experiments.Taking the shale reservoirs of Silurian Longmaxi Formation in Luzhou area of the Sichuan Basin as an example,the effects of in-situ stress difference,natural fracture parameters,branch wellbore spacing,delay detonation time,and angle between branch wellbore and main wellbore on fracture propagation were identified.The results show that the fracture propagation morphology in deflagration fracturing is less affected by the in-situ stress difference when it is 5-15 MPa,and the tendency of fracture intersection between branch wellbores is significantly weakened when the in-situ stress difference reaches 20 MPa.The increase of natural fracture length promotes the fracture propagation along the natural fracture direction,while the increase of volumetric natural fracture density and angle limits the fracture propagation area and reduces the probability of fracture intersection between branch wells.The larger the branch wellbore spacing,the less probability of the fracture intersection between branch wells,allowing for the fracture propagation in multiple directions.Increasing the delay detonation time decreases the fracture spacing between branch wellbores.When the angle between the branch wellbore and the main wellbore is 45°and 90°,there is a tendency of fracture intersection between branch wellbores. 展开更多
关键词 deflagration fracturing multi-branch well fracture propagation law shale reservoir discrete fracture network
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Aggregation-induced Emission-active Hyperbranched Poly (tetrahydropyrimidine)s Synthesized from Multicomponent Tandem Polymerization 被引量:7
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作者 Yuzhang Huang Ping Chen +2 位作者 Bo Wei Rongrong Hu Ben Zhong Tang 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2019年第4期428-436,I0008,共10页
Hyperbranched polymer with highly branched three-dimensional topological structure, a large number of end groups, and multifaceted functionalities have gained much attention, while polymers with aggregation-induced em... Hyperbranched polymer with highly branched three-dimensional topological structure, a large number of end groups, and multifaceted functionalities have gained much attention, while polymers with aggregation-induced emission(AIE) properties become a group of popular luminescent materials recently. The design and synthesis of AIE-active hyperbranched polymers, which combine the advantages of these two types of materials, are attractive but challenging. In this work, four hyperbranched poly(tetrahydropyrimidine)s were synthesized from the metal-free room temperature multicomponent tandem polymerization of diester group-activated internal alkyne,polyfunctional aromatic amines, and formaldehyde in methanol under the catalysis of acetic acid. Through different monomer combination and controlling the monomer loading order, hyperbranched polymers with various topological structures as well as sequences of different functional groups in the polymer backbone were obtained with high molecular weights(up to 3.0 × 10~4 g/mol) in high yields(up to 98%). The hyperbranched poly(tetrahydropyrimidine) emitted faintly in solution, while its luminescence was notably enhanced in the aggregated state, suggesting its typical aggregation-induced emission property. It is anticipated that the multicomponent polymerization may provide a synthetic platform for the construction of hyperbranched polyheterocycles with diverse structures and functionalities. 展开更多
关键词 HYPERBRANCHED polymer MULTICOMPONENT TANDEM POLYMERIZATION Aggregation-induced emission Polyheterocycle
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Synthesis of Functional Hyperbranched Poly(methyltriazolylcarboxylate)s by Catalyst-free Click Polymerization of Butynoates and Azides 被引量:3
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作者 Mu-Ning Lang Wei-Wen Chi +4 位作者 Ting Han Qing-Zhen Zhao Hong-Kun Li Ben Zhong Tang Yong-Fang Li 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2020年第11期1171-1177,I0005,共8页
Azide-alkyne click polymerization has become a powerful tool for polymer synthesis.However,the click polymerization between internal alkynes and azides is rarely utilized to prepare functional polymers.In this work,th... Azide-alkyne click polymerization has become a powerful tool for polymer synthesis.However,the click polymerization between internal alkynes and azides is rarely utilized to prepare functional polymers.In this work,the polymerization reactions of activated internal alkyne monomers of tris(2-butynoate)s(1)with tetraphenylethene-containing diazides(2)were performed in dimethylformamide(DMF)under simple heating,affording four hyperbranched poly(methyltriazolylcarboxylate)s(hb-PMTCs)with high molecular weights(A4W up to 2.4 x 104)and regioregularities(up to 83.9%)in good yields.The hb-PMTCs are soluble in common organic solvents,and thermally stable with 5%weight loss temperatures up to 400℃.They are non-emissive in dilute solution,but become highly emissive in aggregated state,exhibiting aggregationinduced emission characteristics.The polymers can generate fluorescent photopatterns with high resolution,and can work as fluorescent sensors to detect nitroaromatic explosive with high sensitivity. 展开更多
关键词 Click polymerization Hyperbranched polymer Aggregation-induced emission Explosive detection Photopattern
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The Model of "Party Branch +" in Promoting Industrial Poverty Alleviation in Poverty-stricken Mountainous Areas of China: A Case Study of Xundian in Yunnan Province
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作者 Zhiqing YAN Zisheng YANG 《Asian Agricultural Research》 2019年第6期71-76,84,共7页
The integration and development of grass-roots Party organizations and accurate poverty alleviation is the focus in social development in the new period. This is also a new measure explored by the CPC Central Committe... The integration and development of grass-roots Party organizations and accurate poverty alleviation is the focus in social development in the new period. This is also a new measure explored by the CPC Central Committee in the new historical period to solve rural reform and extricate the poor from poverty,and can effectively enhance the enthusiasm of the masses in poverty alleviation and development work. Xundian Hui and Yi Autonomous County is located in the mountainous area of northeast Yunnan Province. It is one of the 592 national key counties for poverty alleviation and development and one of the 38 continuous development counties in Wumeng Mountain area. Since the implementation of the accurate poverty alleviation strategy,Xundian County insists on getting rid of poverty to grasp the overall situation of county economic and social development,focus on the actual situation of the county people,and conscientiously grasp the key of industrial poverty alleviation. It regards industry as the fundamental driving force to realize poverty alleviation from " blood transfusion" to " blood creation",and innovates the model of " Party branch +" to help the poor out of poverty by industry. It has selected 187 agricultural enterprises( cooperatives,large households) to achieve full coverage of all registered poor households,and achieved remarkable results. It has realized that each poor village has one to two leading industries,and each poor household has one to two industrial income projects,having led 30 500 poor households to increase their average income by more than 1 850 yuan. The final incidence of poverty decreased from 26. 93% in 2014 to 0. 35% at the end of 2017,becoming one of the first counties in Yunnan Province to get rid of poverty. It is also the only county in Yunnan Province that has won the Antipoverty Organization Innovation Award of the State Council. Based on field research and interviews,this paper analyzes and summarizes the specific methods,main achievements,practical experience and popularization and application measures of Xundian County " Party Branch +" to promote industrial poverty alleviation,so as to provide necessary reference for accurate poverty reduction and poverty alleviation in similar mountainous areas of Yunnan Province and other provinces. 展开更多
关键词 Accurate POVERTY alleviation "Party Branch+" INDUSTRIAL POVERTY alleviation Model Xundian Hui and Yi Autonomous County
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Map-based cloning of a novel QTL qBN-1 influencing branch number in soybean[Glycine max(L.)Merr.] 被引量:5
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作者 Sobhi F.Lamlom Yong Zhang +5 位作者 Bohong Su Haitao Wu Xia Zhang Jindong Fu Bo Zhang Li-Juan Qiu 《The Crop Journal》 SCIE CAS CSCD 2020年第5期793-801,共9页
Branch number(BN)is an important agronomic attribute related to the plant architecture,adaptability,and yield of soybean.To date,few studies ofBNhave been conducted to elucidate its genetic background.We aimed to loca... Branch number(BN)is an important agronomic attribute related to the plant architecture,adaptability,and yield of soybean.To date,few studies ofBNhave been conducted to elucidate its genetic background.We aimed to localize genetic factors affecting BN using segregating populations derived fromthe high-branching cultivar‘Kennong24’(KN24)and the low-branching cultivar‘Kenfeng19’(KF19).Composite interval mapping analysis detected a QTL(qBN-1)on chromosome 6 between the SSR markers BARCSOYSSR_06_0993 and BARCSOYSSR_06_1070 using an F2 population.To fine-map qBN-1,a RIL population was developed and genotyped with 14 SSRmarkers located in the QTL region.qBN-1 was localized to a 115.67-kb interval flanked by markers BARCSOYSSR_06_1048 and BARCSOYSSR_06_1053.The QTL was further confirmed using backcross populations of size 1305(BC2F2 with KN24 as a recurrent parent)and 1712(BC3F2 with KF19 as a recurrent parent).The fine-mapping region of qBN-1 contained only two candidate genes,Glyma.06G208800 and Glyma.06G208900,whose expression patterns were investigated by qRT-PCR.Compared to Glyma.06G208800 gene expression,Glyma.06G208900 showed the highest expression of the two genes and showed a significant difference in expression between high-and low-branching genotypes in either axillary meristem or shoot apical meristem,and showed opposite expression patterns in the two tissues at V4 and R1 stages.These results identify Glyma.06G208900 as a novel candidate gene controlling BN.Taken together,the results of this study provide a foundation for cloning and functional analysis of the qBN-1 gene and for the improvement of BN bymarker-assisted selection in soybean breeding. 展开更多
关键词 SOYBEAN CULTIVAR GLYCINE
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Shareable Instruments and Observatories for the Joint Research Center on Space Weather of the Siberian Branch of Russian Academy of Sciences and Chinese Academy of Sciences
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作者 G.Y.Smolkov 《空间科学学报》 CAS CSCD 北大核心 2005年第5期345-350,共6页
Presented are the ideas and proposals in regards to the pooling of by RAS, SB, ISTP, and CSSAR,CAS toward coordinated usage of existing ground-based and orbiting helio-geophysical observatories, single large installat... Presented are the ideas and proposals in regards to the pooling of by RAS, SB, ISTP, and CSSAR,CAS toward coordinated usage of existing ground-based and orbiting helio-geophysical observatories, single large installations as well as creating, forecasting services and new observing facilities, in the interests of achieving a profitable activity of the China-Russia Joint Research Center on Space Weather (JRCSW). 展开更多
关键词 天文台 空间气象 西伯利亚 俄罗斯 中国 科学研究 数据库 气象预报
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The Relationship between Consumption of Fast Food with Level of Serum Folat among Nursing Students of Islamic Azad University, Tehran Medical Sciences Branch in 2016
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作者 Naghibeiranvand Mehran Moshtagheshgh Zahra 《International Journal of Clinical Medicine》 2017年第5期338-343,共6页
In recent decades, substantial increase in average weight of individuals has been seen in rich countries. Such changes are the result of significant changes in pattern of people’s lives. One of these issues is increa... In recent decades, substantial increase in average weight of individuals has been seen in rich countries. Such changes are the result of significant changes in pattern of people’s lives. One of these issues is increasing levels in consumption of fast foods or processed foods. According to experts, the consumption of processed foods, because of having high-calories and trans-fatty acids, is fattening and harmful. In this study, the researchers after obtaining permission from the ethics committee and head of the School of Nursing, introduced themselves to nursing students then, samples were randomly selected among those who are eligible for the study. Before performing to complete the questionnaire and relevant experiments, testimonial were asked from the subjects. At the end of the study, results were suggested that, levels of Serum folate between males and females and also among married and single people were equivalent. Level of Serum folate among those students who usually have anemia in their families is significantly lower than those ones who have not anemia in their families (P = 0.003). There was a significant relationship between age and semester with levels of folate (P i.e. by increasing age and educational terms, levels of serum folate would be reduced. The level of serum folate among students who smoke is lesser than those do not (P = 0.001). 展开更多
关键词 Fast FOOD SERUM Folate NURSING Students
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Miniaturization and Second Harmonic Suppression of Branch-Line Coupler Using Four Open-End Stubs
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作者 Ali Reza Hazeri Tayeb Faraji 《通讯和计算机(中英文版)》 2010年第5期64-67,共4页
关键词 支线耦合器 谐波抑制 小型化 存根 分枝 设计方法 模态分析 分支机构
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Actin gene family in Branchiostoma belched
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作者 FENG Jun 《科学教育与博物馆》 2016年第1期28-36,共9页
Actin is a highly conserved cytoskeletal protein that is found in essentially all eukaryotic cells,which plays a paramount role in several basic functions of the organism, such as the maintenance of cellshape, cell di... Actin is a highly conserved cytoskeletal protein that is found in essentially all eukaryotic cells,which plays a paramount role in several basic functions of the organism, such as the maintenance of cellshape, cell division, cell mobility and muscle contraction. However, little is known about actin gene family inChinese amphioxus (Branchiostoma belcheri). Here we systemically analyzed the actin genes family inBranchiostoma belched and found that amphioxus contains 33 actin genes. These genes have undergoneextensive expansion through tandem duplications by phylogenetic analysis. In addition, we also providedevidence indicating that actin genes have divergent functions by specializing their EST data in both Bran-chiostoma belched and Branchiostoma florida. Our results provided an alternative explanation for the evolu-tion of actin genes, and gave new insights into their functional roles. 展开更多
关键词 ACTIN GENE FAMILY AMPHIOXUS evolution EST data
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Children with Sickle Cell Disease in Northern Benin: Follow up of a Cohort at the Borgou/Alibori Branch of Integrated Medical Healthcare Center for Infants and Pregnant Women with Sickle Cell Disease from 2017 to 2022
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作者 Falilatou Agbeille Mohamed Alphonse Noudamadjo +6 位作者 Médétinmè Gérard Kpanidja Yémalin Zinsou François Anikè Akinola Kpedio Clarisse Marie Chantal Bossa Julien Didier Adédémy Joseph Agossou 《Open Journal of Pediatrics》 2024年第3期445-458,共14页
Introduction: Sickle cell disease is a public health problem in sub-Saharan Africa. A national referral center for the management of infants and pregnant women with sickle cell disease (CPMI-NFED) was created three de... Introduction: Sickle cell disease is a public health problem in sub-Saharan Africa. A national referral center for the management of infants and pregnant women with sickle cell disease (CPMI-NFED) was created three decades ago in Cotonou, in the south of Benin with two regional branches including that of Parakou in the North for better access of patients to specialized care. This work is a review of five years of activities in order to describe the epidemiological, clinical, hematological and evolutionary profiles of the children followed up in the said branch. Method: This was a descriptive and retrospective cross-sectional study on the medical records of children with sickle cell disease, followed up at the regional branch of CPMI-NFED in Borgou/Alibori from June 1, 2017 to May 31, 2022. The variables studied were epidemiological, clinical, biological and evolutionary. Results: A total of 101 children with sickle cell disease were included in the study, including 78 homozygous SS (77.2%) and 23 heterozygous SC (22.8%). Their mean age at inclusion was 51.2 ± 37.6 months [6 - 204]. The sex ratio was 1.4. Vaso-occlusive crises were the main diagnostic circumstances in 42.3% of homozygotes. More than half of the children (51.5%) had a regular follow-up. The average baseline level of hemoglobin (Hb) in homozygous children was 8.8 ± 1.4 g/dl [5.8 - 11.5];and the rate of Hb S varied between 61.9 and 94.7%. In heterozygous SC children, the mean baseline level of Hb was 10.7 ± 0.6 g/dl [9.7 - 11.5]. Acute complications observed during follow-up were dominated by pneumonia and vaso-occlusive crises in both phenotypes. The overall mortality was 3% and only affected homozygous patients. Conclusion: On average, three out of four children were homozygous in our cohort. The main acute complications were infectious and vaso-occlusive. The mortality only affected homozygous carriers. Specialized follow-up has contributed to improving the quality of life of children with sickle cell disease. This could be implemented on a large scale for better survival of children with sickle cell disease. 展开更多
关键词 Sickle Cell Disease CHILDREN CPMI-NFED Parakou BENIN
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Ecological Environment Monitoring Station of Yanshan Branch,Wenshan Prefecture Ecological Environment Bureau,Yunnan Province,Yanshan 663100,China
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作者 Sumei LI Guofang ZENG +1 位作者 Lei YIN Zhangyue WANG 《Meteorological and Environmental Research》 2024年第5期14-16,20,共4页
How ecological environmental monitoring provides scientific and technological strength for ecological environmental management was studied.In recent years,the Ecological Environment Monitoring Station of Yanshan Branc... How ecological environmental monitoring provides scientific and technological strength for ecological environmental management was studied.In recent years,the Ecological Environment Monitoring Station of Yanshan Branch,Wenshan Prefecture Ecological Environment Bureau,Yunnan Province has developed into a provincial environmental education base,a provincial science education base,and a national environmental protection facility open to the public by relying on monitoring equipment and facilities,personnel training,monitoring and law enforcement interaction,analysis of abnormal data,and countermeasures and suggestions were put forward for the problems in the development. 展开更多
关键词 Ecological environment monitoring Ecological environment management Scientific and technological strength
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基于高精度地质建模技术的断层侧向封闭性评价方法——以辽河坳陷兴隆台构造带太古界潜山油气藏为例
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作者 李滨 闵忠顺 +3 位作者 孟令娜 张源李 尹剑峰 周培杰 《岩性油气藏》 北大核心 2026年第1期126-135,共10页
Allan图分析对于断层封闭性的研究具有重要意义。以辽河坳陷兴隆台构造带太古界潜山油气藏为例,综合测录井、三维地震和实验分析测试资料,提出了一种基于高精度地质建模技术的改进Allan图法,用于分析断层封闭性。研究结果表明:(1)基于井... Allan图分析对于断层封闭性的研究具有重要意义。以辽河坳陷兴隆台构造带太古界潜山油气藏为例,综合测录井、三维地震和实验分析测试资料,提出了一种基于高精度地质建模技术的改进Allan图法,用于分析断层封闭性。研究结果表明:(1)基于井-震联合建立的高精地质模型可解决井位数据缺失的问题,在精细剖析变质岩潜山各个区域的岩性发育情况及造缝能力的基础上,高精地质模型可准确刻画断层两侧的地层接触关系和岩性分布规律,经人工检查和调整可形成最终的改进Allan图。(2)研究区断面上共存在6种岩性对接模式,其中具备良好封闭性的对接模式包含角砾岩-泥岩、混合岩-泥岩、混合岩-片麻岩、混合岩-角砾岩、角砾岩-角砾岩,区外围断层F3、F5全封闭,区内渗漏点海拔为-4 390 m。(3)结合模糊数学方法、现场流体分布进行了交叉检验,各个区域分析结果与改进Allan图法分析的断层侧向封闭性吻合度高,说明该方法在变质岩潜山表现出优异的适用性和准确性,具有较高的应用价值。 展开更多
关键词 改进Allan图法 断层封闭性 储气库 高精度地质建模 太古界潜山 兴隆台构造带 辽河坳陷
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参蛤补肺汤联合化疗治疗利福平敏感复治肺结核临床观察
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作者 陈代平 方明珠 +2 位作者 程瑶 赵丽华 李林 《辽宁中医杂志》 北大核心 2026年第1期91-95,共5页
目的探究参蛤补肺汤联合西药化疗治疗利福平敏感复治肺结核的临床效果。方法将136例利福平敏感型复治肺结核患者随机分成两组,包括治疗组(68例)和对照组(68例),其中治疗组采用标准化的治疗方案:(2HRZS(L)E/6HRE)联合参蛤补肺汤;对照组... 目的探究参蛤补肺汤联合西药化疗治疗利福平敏感复治肺结核的临床效果。方法将136例利福平敏感型复治肺结核患者随机分成两组,包括治疗组(68例)和对照组(68例),其中治疗组采用标准化的治疗方案:(2HRZS(L)E/6HRE)联合参蛤补肺汤;对照组则单用标准化的治疗方案。观察两组在治疗后2、5个月和疗程结束时的痰菌转阴、病灶吸收及空洞闭合情况,计算两组的治疗成功率;观察两组在治疗后的临床症状及免疫功能改善情况;通过多因素回归分析治疗成功的相关因素。结果治疗组在各个观察点的细菌转阴率均高于对照组(P<0.05),治疗组的治疗成功率为88.2%(60/68),高于对照组的72.1%(49/68)(P<0.05);在疗程结束后,治疗组的胸部X线病灶吸收显效率高于对照组(P<0.05),临床症状改善快于对照组(P<0.05),T淋巴细胞CD_(4)^(+)/CD_(8)^(+)比值高于对照组(P<0.05);治疗过程中,治疗组不良反应发生率低于对照组(P<0.05);治疗前患者为多耐药是治疗成功的独立危险因素,而使用参蛤补肺汤辅助治疗则是治疗成功的独立保护因素。结论使用参蛤补肺汤辅助治疗利福平敏感的复治肺结核患者,可促进细菌转阴、提高治疗成功率、加速病灶吸收、促进症状改善、改善细胞免疫、减少不良反应,是更为优化的复治肺结核治疗方案。 展开更多
关键词 复治肺结核 参蛤补肺汤 利福平敏感 方案评价 疗效比较研究
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柴达木盆地台南地区第四系滩-坝砂体特征及控制因素
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作者 易定红 刘应如 +6 位作者 吴颜雄 奎明清 李积永 李红哲 涂加沙 张婷静 徐晓玲 《石油与天然气地质》 北大核心 2026年第1期108-123,共16页
为深入评价柴达木盆地台南地区滨-浅湖滩-坝的天然气勘探开发前景,通过岩心观察和钻(测)井资料分析,结合岩石薄片、X射线衍射全岩矿物测试、粒度累积概率曲线、黏土矿物组合、泥岩岩屑氯离子含量和砂(灰)/地比等参数,系统研究了第四系... 为深入评价柴达木盆地台南地区滨-浅湖滩-坝的天然气勘探开发前景,通过岩心观察和钻(测)井资料分析,结合岩石薄片、X射线衍射全岩矿物测试、粒度累积概率曲线、黏土矿物组合、泥岩岩屑氯离子含量和砂(灰)/地比等参数,系统研究了第四系七个泉组Ⅱ层系滩-坝沉积环境、平面展布、发育演化和控制因素。结果表明:①台南地区主要发育碎屑岩滩-坝,偶见碳酸盐岩滩-坝。碎屑岩滩-坝以含岩屑长石质细砂岩-粉砂岩为主,粒度曲线主要为“一跳一悬”两段式(占64.4%),其次为多段式(占11.9%)。发育水平层理、波状层理和低角度交错层理。碳酸盐岩滩-坝主要为具有粉-泥晶结构的含泥、含粉砂泥晶灰岩。②七个泉组Ⅱ层系碎屑岩滩-坝发育,单层厚度平均值为2.13 m,砂/地比平均值为0.34,单坝体规模较小,主要位于背斜核部,呈条带状展布。背斜东翼坝呈NE-SW向,西翼呈NW-SE向。碳酸盐岩滩-坝规模较小,灰/地比平均值为0.37,呈环形分布于背斜核部。③湖盆水体主要为半咸水-咸水,局部出现盐水。气候干旱寒冷且波动性强,黏土矿物主要为伊利石(占44.2%),其次为伊/蒙混层(占22.9%)和绿泥石(占19.6%)。台南地区滩-坝发育且迁移摆动明显,背斜两翼滩-坝演化差异大。干旱气候环境和低幅度同沉积背斜是滩-坝发育的主控因素。 展开更多
关键词 沉积环境 沉积特征 滩-坝砂体 七个泉组 台南地区 柴达木盆地
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深度域地震-地质导向技术在古龙页岩油水平井导向中的应用
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作者 赵海波 黄丛 +3 位作者 乔卫 王团 李奎周 王宏强 《大庆石油地质与开发》 北大核心 2026年第1期127-136,共10页
水平井钻井已经成为页岩油经济有效开采的主要手段,水平井导向技术是水平井钻井成功的关键技术。以往地质导向技术利用水平井实钻曲线与导眼井曲线拟合预测井底位置,结合地震预测钻井前方构造趋势变化,时间域地震无法直接预测出钻井前... 水平井钻井已经成为页岩油经济有效开采的主要手段,水平井导向技术是水平井钻井成功的关键技术。以往地质导向技术利用水平井实钻曲线与导眼井曲线拟合预测井底位置,结合地震预测钻井前方构造趋势变化,时间域地震无法直接预测出钻井前方构造倾角等参数,而深度域地震受速度的影响,常会出现地震预测井底所在层位与实钻层位不符的问题,无法及时更新深度域地震,影响水平井有效箱体钻遇率。为开展深度域地震-地质导向技术研究,满足页岩油大规模水平井勘探开发的需求,充分利用地震、测井以及现场实时钻井数据,建立地震地质导向模型,通过实钻曲线与导眼井曲线拟合调整导向模型,确定井底在地下准确位置,利用导向模型层位与地震解释层位匹配构建实时更新的速度场,自动更新深度域地震剖面。该技术解决了深度域地震导向,地震剖面无法及时更新问题,确保导向模型标志层位与深度域地震标志层位完全一致,提高了地震导向钻井前方构造倾角预测的准确性,在古龙页岩油导向中具有了较好的效果,已经完钻的55口水平井,一类箱体钻遇率达到97%。研究成果可推广到其他领域水平井导向过程中。 展开更多
关键词 地震-地质导向技术 古龙页岩油 速度场 深度域 水平井
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井下低熔点合金封堵套管的密封性
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作者 查春青 陶文超 +5 位作者 朱治国 李栋 郑建锋 王政国 柳贡慧 汪伟 《中国石油大学学报(自然科学版)》 北大核心 2026年第1期212-221,共10页
针对井下低熔点金属封堵中Bi基合金与套管之间密封性能,构建合金塞成型试验及气密封试验装置,开展合金塞与套管结合后的承压能力与气密封性能试验,利用光学显微镜分析密封面的微观结构,研究轴向压力及环境温度对合金塞密封性能的影响。... 针对井下低熔点金属封堵中Bi基合金与套管之间密封性能,构建合金塞成型试验及气密封试验装置,开展合金塞与套管结合后的承压能力与气密封性能试验,利用光学显微镜分析密封面的微观结构,研究轴向压力及环境温度对合金塞密封性能的影响。结果表明:所形成的合金塞密封性能受环境温度影响较大,随着环境温度升高,合金塞/套管之间结合能力降低,其承压能力下降;在合金塞凝固成型过程中,通过施加轴向压力,有益于提高合金塞承压与气密封能力;当合金塞被推动后,其与套管内壁会发生剪切破坏移动,但其气密封性能不会完全破坏;Bi基合金作为一种井下套管封堵的新型材料,能够通过材料本体的膨胀性来实现套管的封堵。 展开更多
关键词 Bi基合金 密封性能 合金塞成型 轴向压力 套管封堵
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燕辽裂陷带北部中元古界烃源岩研究进展综述
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作者 孙求实 李晓海 +2 位作者 刘邦 孙守亮 宗文明 《西北地质》 北大核心 2026年第1期216-230,共15页
近几十年来元古宙早期生命演化基础性研究取得重大进展,随着全球范围内多处中元古界原生油气藏的发现和商业化开发,中元古界已成为重要的油气勘探目的层。中国北方燕辽裂陷带,尤其是北部冀北、辽西两坳陷中元古界分布广、沉积厚度大,具... 近几十年来元古宙早期生命演化基础性研究取得重大进展,随着全球范围内多处中元古界原生油气藏的发现和商业化开发,中元古界已成为重要的油气勘探目的层。中国北方燕辽裂陷带,尤其是北部冀北、辽西两坳陷中元古界分布广、沉积厚度大,具备形成与富集规模性油气资源的条件。笔者从烃源层生烃潜力、油源对比研究、成藏期次3个方面总结了燕辽裂陷带北部地区中元古界油气资源研究进展。结合收集和自测烃源岩样品数据,对冀北、辽西6套主要烃源层沉积特征及生烃潜力进行评价。研究发现,洪水庄组页岩分布范围广,沉积厚度大,受后期蚀变及构造破坏小,具有好的生烃潜力,是燕辽裂陷带北部中元古界最主要的烃源层。因此,笔者建议将燕辽裂陷带北部中元古界油气勘探的重点着眼于找寻辽西坳陷洪水庄组供油的构造稳定圈闭。 展开更多
关键词 油气勘查工程 生烃潜力 烃源岩 中元古界 燕辽裂陷带北部
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基于IoT技术的寒地黑土质量信息监测系统
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作者 葛宜元 孙道起 +4 位作者 孟庆祥 王囡囡 高士军 苏安双 王淼 《农机化研究》 北大核心 2026年第1期226-232,267,共8页
寒地黑土是我国东北地区的重要农业资源,土壤质量和环境状况直接影响粮食产量和质量。为有效监测和管理寒地黑土质量和环境变化情况,构建了一种基于物联网(IoT)技术的寒地黑土质量信息监测系统。该系统通过传感器采集土壤湿度、温度、p... 寒地黑土是我国东北地区的重要农业资源,土壤质量和环境状况直接影响粮食产量和质量。为有效监测和管理寒地黑土质量和环境变化情况,构建了一种基于物联网(IoT)技术的寒地黑土质量信息监测系统。该系统通过传感器采集土壤湿度、温度、pH值和氮磷钾等养分数据,并利用无线网络传输至数据处理中心,进行数据存储、分析和可视化展示。设计地力评价模块,根据寒地作物种植需求,选择适合寒地黑土的地力评价因子,以选定的评价指标为基本对象,通过选取层次分析法进行指标权重分析,利用模糊综合评价法进行隶属度计算以进行寒地黑土信息评价;系统可实现土壤质量信息的实时监测,数据查询、分析、评价和下载。验证试验结果表明,该系统在寒地环境中数据测量稳定,土壤温度测量精度达到±0.3℃,湿度为±0.26%RH,pH值为±0.03,系统阈值报警响应时间平均为15 s。该系统实现了寒地黑土质量信息的中长期稳定监测,对地力的评价符合农业部标准,可为肥料施用等农田管理提供科学合理的建议,进而提高管理效率,实现作物增产增收。 展开更多
关键词 寒地黑土 质量监测 MCGS IoT技术 可视化 地力评价
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基于对标管理和节点分析的煤层气集气系统站场工艺优化方法
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作者 孟凡华 张博 +3 位作者 刘松群 吴春升 屈丽彬 王子辉 《油气田地面工程》 2026年第1期60-65,共6页
在企业管理活动中,对标管理和节点分析是企业不断改进和获得竞争优势的最重要管理方式。山西煤层气分公司自2021年起,按照中国石油天然气股份有限公司煤层气田管理指标开展对标管理工作,发现了综合用能高的主要问题。为进一步提升煤层... 在企业管理活动中,对标管理和节点分析是企业不断改进和获得竞争优势的最重要管理方式。山西煤层气分公司自2021年起,按照中国石油天然气股份有限公司煤层气田管理指标开展对标管理工作,发现了综合用能高的主要问题。为进一步提升煤层气田地面系统运行管理水平,构建了一套具有二级节点、41项管控参数的煤层气集气系统井站管理体系,建立了节点分析和对标管理融合的工作流程,在此基础上,通过分析和论证,实施站场优化4处,实现沁水盆地煤层气田站场运行参数逐步提升。2021至2023年单位气田气生产综合能耗、单位气田气采集输综合能耗、单位气田气处理综合能耗逐年下降,完成了2021年的能耗指标低于平均值到2023年指标接近先进值的转变。 展开更多
关键词 煤层气 集气系统 对标管理 节点分析 工艺优化
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维奈克拉联合HEA方案治疗KMT2A基因重排急性髓系白血病患者疗效观察
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作者 陶善东 问蓉 +5 位作者 李佳欣 郑鑫琪 史文婷 丁邦和 于亮 王春玲 《中国实验血液学杂志》 北大核心 2026年第1期1-6,共6页
目的:观察维奈克拉联合HEA(VHEA)方案诱导治疗伴KMT2A基因重排的急性髓系白血病(AML)的治疗反应率与安全性。方法:采用VHEA方案[维奈克拉100mgd1,200mgd2,400mgd3-14;高三尖杉酯碱2mg/(m^(2)·d),d1-7;依托泊苷100mg/d,d1-5;阿糖胞... 目的:观察维奈克拉联合HEA(VHEA)方案诱导治疗伴KMT2A基因重排的急性髓系白血病(AML)的治疗反应率与安全性。方法:采用VHEA方案[维奈克拉100mgd1,200mgd2,400mgd3-14;高三尖杉酯碱2mg/(m^(2)·d),d1-7;依托泊苷100mg/d,d1-5;阿糖胞苷100mg/(m^(2)·d),d1-7]治疗6例伴KMT2A基因重排AML患者,观察该方案的缓解率与安全性。结果:6例患者包括3例复发难治与3例初治患者,经1个疗程诱导化疗后,5例患者均获得完全缓解(CR),其中3例流式细胞术检测微小残留病(MRD)<1.0×10^(-3),3例PCR检测MRD均为0.00%,1例移植后13个月复发患者未能评价疗效即并发肺部感染死亡。3例在CR1行异基因造血干细胞移植(allo-HSCT),1例于移植后12个月复发,总生存时间20个月;另2例目前仍处于无病生存状态,分别随访15和5个月。2例患者未接受allo-HSCT,1例生存4个月后因复发死亡,1例目前CR状态维持化疗中。VHEA方案治疗6例KMT2A基因重排AML,总CR率为83.3%(5/6),无治疗相关死亡发生,骨髓抑制、感染等化疗相关不良反应在可控制范围。结论:VHEA方案能够显著提高KMT2A基因重排AML患者的CR率,安全性良好,该方案可能是初治与复发难治伴KMT2A基因重排AML患者诱导缓解化疗的一种较好的选择。 展开更多
关键词 维奈克拉 VHEA方案 KMT2A 急性髓系白血病 异基因造血干细胞移植
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