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南美奥连特盆地白垩系Napo组Main-M1亚段沉积体系重建及油气勘探意义 被引量:1
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作者 李发有 班舒悦 +9 位作者 王光付 孙建芳 丁峰 孙钰 王腾宇 徐海 陈诗望 夏昌盛 郑乃熙 鲍志东 《古地理学报》 CAS CSCD 北大核心 2024年第1期17-27,共11页
厄瓜多尔奥连特盆地是南美安第斯前陆盆地群中最重要的含油气盆地之一,上白垩统Napo组Main-M1亚段是目前勘探开发的主力层位之一,其沉积环境一直存在争议,沉积体系及演化过程尚不明确。本研究基于岩心、测录井等资料,针对Main-M1亚段沉... 厄瓜多尔奥连特盆地是南美安第斯前陆盆地群中最重要的含油气盆地之一,上白垩统Napo组Main-M1亚段是目前勘探开发的主力层位之一,其沉积环境一直存在争议,沉积体系及演化过程尚不明确。本研究基于岩心、测录井等资料,针对Main-M1亚段沉积时期的主要沉积微相类型、沉积体系及演化过程进行了研究。结果表明:研究区位于水动力条件复杂的海陆过渡环境,在东部发育潮汐三角洲,向西部逐渐过渡为浅海陆棚环境;研究区内主要识别出水下分流河道、水下分流河道间、潮汐水道、潮汐沙坝、潮汐沙坪、潮汐水道间等8类沉积微相。根据岩电特征,进一步将Main-M1亚段划分为3个小层。通过分析3个小层的岩性组合演变特征,确定在Main-M1亚段沉积时间内,Auca古隆起逐渐形成,同时挠曲作用导致相对海平面升高,3个小层在垂向上呈水体逐渐变深、潮汐三角洲前缘不断向陆地退缩的形式;基于对Main-M1亚段沉积时期潮汐三角洲—浅海陆棚沉积体系的重建,研究区东部的水下分流河道及前缘沙坝也被认为具有一定的岩性油气藏勘探潜力。 展开更多
关键词 潮汐三角洲 陆棚 沉积微相 沉积模式 main-M1亚段 奥连特盆地 南美洲
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南美奥连特盆地坎潘阶碳酸盐岩建隆的识别及科迪勒拉运动早期抬升对Main-M1储集层沉积的控制作用 被引量:1
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作者 丁峰 王光付 +6 位作者 孙建芳 孙钰 李发有 薛明喜 吴洁 班舒悦 鲍志东 《古地理学报》 CAS CSCD 北大核心 2024年第1期5-16,共12页
厄瓜多尔奥连特盆地Main-M1砂岩储集层是该盆地近年来重要的构造-岩性圈闭勘探目的层系,寻找砂体和岩性尖灭带是Main-M1砂岩勘探的关键。该盆地为晚白垩世弧后热沉降盆地和新生代前陆盆地的叠合盆地,在构造上分为西部逆冲褶皱带、中部... 厄瓜多尔奥连特盆地Main-M1砂岩储集层是该盆地近年来重要的构造-岩性圈闭勘探目的层系,寻找砂体和岩性尖灭带是Main-M1砂岩勘探的关键。该盆地为晚白垩世弧后热沉降盆地和新生代前陆盆地的叠合盆地,在构造上分为西部逆冲褶皱带、中部前渊带和东部斜坡带,在前渊带发育一系列近N-S走向长轴背斜。综合观察和分析发现,在研究区内长轴背斜上生长了1个碳酸盐岩建隆,地震上具有明显的边界反射形成丘状外观和较连续的弱振幅内部反射,测井上具有厚层、近箱型低GR响应特征。该建隆表明在其沉积的坎潘阶时期,长轴背斜已经开始抬升,将背斜顶部推升至古水面附近,形成建隆局部生长的条件。压实回剥方法恢复古地貌证实,长轴背斜在坎潘阶早期开始发育,构造抬升幅度为7~10 m。由于构造抬升和建隆发育始于Main-M1沉积前,抬升古地貌可影响砂岩沉积。根据背斜上数十口已钻井Main-M1砂体厚度统计,发现背斜顶部砂岩储集层整体较发育,但古建隆顶部砂层厚度减薄或者缺失,在背斜的南部延伸段,构造顶部砂岩缺失,仅在东部侧翼富集。提出了近N-S向背斜古地貌影响Main-M1砂体沉积,使砂岩于富集于构造下倾方向的控砂模式。该模式可形成上倾尖灭型构造-岩性圈闭,从而提供了通过古地貌恢复在奥连特盆地前渊带寻找新圈闭的勘探思路。 展开更多
关键词 奥连特盆地 科迪勒拉运动 碳酸盐岩建隆 古地貌 main-M1储集层 构造-岩性圈闭
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Strong shock propagation for the finite-source circular blast in a confined domain
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作者 Qihang MA Kaileong CHONG +1 位作者 Bofu WANG Quan ZHOU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第6期1071-1084,共14页
The circular explosion wave produced by the abrupt discharge of gas from a high-temperature heat source serves as a crucial model for addressing explosion phenomena in compressible flow.The reflection of the primary s... The circular explosion wave produced by the abrupt discharge of gas from a high-temperature heat source serves as a crucial model for addressing explosion phenomena in compressible flow.The reflection of the primary shock and its propagation within a confined domain are studied both theoretically and numerically in this research.Under the assumption of strong shock,the scaling law governing propagation of the main shock is proposed.The dimensionless frequency of reflected shock propagation is associated with the confined distance.The numerical simulation for the circular explosion problem in a confined domain is performed for validation.Under the influence of confinement,the principal shock wave systematically undergoes reflection within the domain until it weakens,leading to the non-monotonic attenuation of kinetic energy in the explosion fireball and periodic oscillations of the fireball volume with a certain frequency.The simulation results indicate that the frequency of kinetic energy attenuation and the volume oscillation of the explosive fireball align consistently with the scaling law. 展开更多
关键词 explosion CONFINEMENT main shock frequency
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Minimally Invasive Total Arterial Coronary Artery Bypass Grafting in Left Main Stem Disease
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作者 Pradeep Nambiar Radwan Husseini Prashant Sagar 《World Journal of Cardiovascular Surgery》 2024年第7期107-114,共8页
Objective: The aim was to show that Minimally Invasive total arterial revascularization for left main stem coronary artery disease, via a left anterior Mini thoracotomy using bilateral internal thoracic arteries is fe... Objective: The aim was to show that Minimally Invasive total arterial revascularization for left main stem coronary artery disease, via a left anterior Mini thoracotomy using bilateral internal thoracic arteries is feasible, reproducible and safe. Further, there has been no exclusive data or experience with minimally invasive coronary artery bypass grafting in left main stem disease. Methods: From April 2019 to March 2024, 41 patients with left main stem stenosis, left main equivalent disease and unprotected left main with triple vessel disease underwent off pump minimally invasive multivessel coronary artery bypass grafting using either in situ pedicled Bilateral Internal Thoracic arteries or Left and Right Internal Thoracic artery Y composite conduits at three centers. Bilateral Internal Thoracic arteries were harvested under direct vision. All patients had an Intra-Aortic Balloon Pump inserted via the femoral artery prior to induction of anesthesia, to prevent any hemodynamic instability, arrhythmias, and was removed following completion of the procedure in the operating room without any complications. Efficacy and outcomes were evaluated by i) Primary (MACCE)-Major Adverse Cardiac and Cardiovascular events and ii) Secondary outcome measures including total length of stay, return to full physical activity and quality of life. Mean follow-up was 1.4 years (Maximum was 2.5 years). Results: 41 patients with left main stem coronary artery stenosis, underwent total arterial revascularization using bilateral internal thoracic arteries. Left main stem stenosis was present in 29 patients, Unprotected left main stem stenosis with triple vessel disease in 7 and left main equivalence in 5 patients. In this cohort, 29 patients with only left main stem stenosis had 2 grafts each, 7 patients with left main and triple vessel disease had 3 grafts and 5 patients with left main equivalent disease had 2 grafts respectively. The average number of grafts was 2.2. One patient was converted to open sternotomy as an emergency because of hemodynamic instability and myocardial revascularization was done on cardiopulmonary bypass (2.2%). The average hospital stay was 3.7 days. Ejection fraction was 45% ± 5%. There was one mortality (2.2%) but no major morbidity. The average ICU and hospital stay was 24 ± 4 hours and 3.7 days. All patients were free from major adverse cardiac and cerebrovascular events at follow-up. Conclusions: Multivessel total arterial revascularization using left and right internal thoracic arteries, was performed via a left anterior Mini thoracotomy on patients with left main stem disease and showed that it was safe, reproducible and will help extend the armamentarium of the surgeon in minimally invasive Coronary artery bypass grafting. Concomitantly it helped enhance the potential for shorter hospital stay, increased survival, decreased morbidity, and earlier return to full activity. Furthermore, the safety, efficacy, and outcomes of minimally invasive coronary artery bypass grafting in this high-risk group evaluated by primary and secondary outcome measures have been good in this study. 展开更多
关键词 Left main Stem Minimally Invasive CABG Bilateral Internal Mammary Arteries
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Analysis of Dry-Wet Climate Change Characteristics and Main Influencing Factors in Main Grain Producing Area of Tibet from 1980 to 2021
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作者 Sangbu ZHUJIE Cunjie ZHANG +3 位作者 Puchi ZHAXI Deji BAIMA Lamu NIMA Ciwang PINGCUO 《Agricultural Biotechnology》 2024年第2期43-49,63,共8页
Based on the daily meteorological observation data of seven meteorological stations in southern Tibet from 1980 to 2021 (April-October), the temporal and spatial variation characteristics and influencing factors of ar... Based on the daily meteorological observation data of seven meteorological stations in southern Tibet from 1980 to 2021 (April-October), the temporal and spatial variation characteristics and influencing factors of aridity index ( AI ) in the growing season of major grain producing areas in Tibet were studied by using climate tendency rate, Mann-Kendal test, Morlet wavelet analysis, GIS hybrid interpolation method, Pearson correlation coefficient, contribution rate analysis and other methods. The results showed that the average AI in the main grain producing areas of Tibet was 1.7, which belonged to the semi-arid area, and the overall trend was decreasing (humidifying) (-0.036/10 a). The linear decreasing trend was different in different regions, and the area around Lhatse County was the most significant (-0.26/10 a). AI had no obvious abrupt change, and had long- and medium-term fluctuation characteristics of 24 years, 6 years. The spatial distribution was uneven, and had the characteristics of ‘shrinking arid area and expanding humid area . The contribution rates of the main climate influencing factors of AI varied in different regions. In general, the contribution rates after quantification was as follows: precipitation (34.9%)>relative humidity (28.4%)>sunshine (19.9%)>maximum temperature (12.4%). 展开更多
关键词 TIBET main production area CLIMATE ARIDITY Contribution rate
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Ground response and failure mechanism of gob-side entry by roof cutting with hard main roof
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作者 ZHU Heng-zhong XU Lei WEN Zhi-jie 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2488-2512,共25页
This study is the result of long-term efforts of the authors’team to assess ground response of gob-side entry by roof cutting(GSERC)with hard main roof,aiming at scientific control for GSERC deformation.A comprehensi... This study is the result of long-term efforts of the authors’team to assess ground response of gob-side entry by roof cutting(GSERC)with hard main roof,aiming at scientific control for GSERC deformation.A comprehensive field measurement program was conducted to determine entry deformation,roof fracture zone,and anchor bolt(cable)loading.The results indicate that GSERC deformation presents asymmetric characteristics.The maximum convergence near roof cutting side is 458 mm during the primary use process and 1120 mm during the secondary reuse process.The entry deformation is closely associated with the primary development stage,primary use stage,and secondary reuse stage.The key block movement of roof cutting structure,a complex stress environment,and a mismatch in the supporting design scheme are the failure mechanism of GSERC.A controlling ideology for mining states,including regional and stage divisions,was proposed.Both dynamic and permanent support schemes have been implemented in the field.Engineering practice results indicate that the new support scheme can efficiently ensure long-term entry safety and could be a reliable approach for other engineering practices. 展开更多
关键词 gob-side entry by roof cutting ground response failure mechanism following mining states control hard main roof
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Acute Left Main Coronary Occlusion Following Transcatheter Aortic Valve Implantation
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作者 Alekhya Abburu Basharat Ahmad +2 位作者 Abdallah Masri David Nery Sharon Rufus 《World Journal of Cardiovascular Diseases》 CAS 2024年第11期695-700,共6页
Background: Aortic stenosis (AS) is caused by either age-related degeneration of aortic valve or congenital malformation of aortic cusps. Severe aortic valve stenosis is a clinically emerging diagnosis in the current ... Background: Aortic stenosis (AS) is caused by either age-related degeneration of aortic valve or congenital malformation of aortic cusps. Severe aortic valve stenosis is a clinically emerging diagnosis in the current world. The three cardinal signs of severe AS are dyspnea, syncope, and angina. Transcatheter aortic valve implantation is one of the safe and effective methods for treating severe aortic valve stenosis, and an alternative to surgery in high-risk patients. Aortic valve calcification and changes after TAVI were specifically assessed by computed tomography. Excessive aortic valve calcification is related to procedural complications. A possible consequence is obstruction of coronary ostia. Heavy calcification of the aortic valve and surrounding structure is an important risk factor for coronary obstruction, heart block, and embolization during aortic valve implantation (TAVI). Here we present a case of an elderly old man, where critical ostial left main coronary artery (LMCA) disease was caused by shifting of a calcium speck rather than obstruction with native leaflet. He was successfully rescued by an emergent CABG. Methods and Results: This is a case of a 69-year-old man with severe calcific aortic stenosis and single-vessel CAD who underwent TAVI with a relatively unremarkable course. Notably, his pre-operative TAVI angiography showed no LMCA stenosis. But 10 days later he presented to the ER with acute myocardial infarction with peak high-intensity troponins, diffuse ST changes, and cardiogenic shock. Urgent coronary angiography and intravascular ultrasound showed critical LMCA stenosis caused by a speck of calcium externally abating the vessel. He underwent emergency coronary artery bypass grafting;intraoperative TEE confirmed the etiology. He had an uneventful postoperative course and was successfully weaned off vasoactive medications. Conclusion: This case illustrates that obstruction of coronary ostia could be a possible complication of TAVI. Calcium distribution should factor in TAVI versus surgical candidacy. Calcium shifting should be watched closely during valve deployment, post-TAVI coronary angiogram should be considered if shifting was significant or suspected to compromise coronary arteries. 展开更多
关键词 TAVI (Transcatheter Aortic Valve Implantation) LMCA (Left main Coronary Artery) CAD (Coronary Artery Disease) TEE (Transoesophageal Echocardiography) Intravascular Ultrasound Severe Calcific Aortic Stenosis CABG (Coronary Artery Bypass Grafting)
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Study on the Countermeasures to Improve the Public Outdoor Leisure and Fitness Function on the Two Rivers and Four Banks in the Main Urban Area of Chongqing
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作者 Yuan Li Dexin Li 《Journal of Architectural Research and Development》 2024年第6期51-57,共7页
The main urban area of Chongqing is surrounded by two rivers and set against each other.With its unique waterfront landscape,it has the resource conditions to become a leisure tourism destination.Intending to enhance ... The main urban area of Chongqing is surrounded by two rivers and set against each other.With its unique waterfront landscape,it has the resource conditions to become a leisure tourism destination.Intending to enhance people’s happiness,improve city quality,and promote Chongqing’s main urban area to become a tourist destination,this paper finds out the existing problems in the construction of public outdoor leisure and fitness facilities on the two rivers and four banks of Chongqing’s main urban area through investigation and analysis based on relevant experiences at home and abroad,takes the value chain theory as the guidance,and to find solutions to the problem.On this basis,combined with the law of economic operation,this paper puts forward the guiding ideology,principles,development goals,functional orientation,and development path for the improvement of public outdoor leisure and fitness on two rivers and four banks in the main city of Chongqing,and accordingly puts forward the policy system and guarantee measures for its improvement. 展开更多
关键词 Two rivers and four banks in the main city of Chongqing Public outdoor recreation and fitness Policy measure
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“Eternal Motion” as a “Form of Movement of a Special Nature” and the Main Condition for the Creation of the Universe
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作者 Avas Khugaev Eugeniya Bibaeva 《Journal of Applied Mathematics and Physics》 2024年第6期2041-2068,共28页
The article hypothesizes that DE and DM (UCM) are a “Form of Motion of a Special Nature”, where “Form of Motion” means “Eternal Motion” as the power of dynamics of different levels and varying degrees of self-su... The article hypothesizes that DE and DM (UCM) are a “Form of Motion of a Special Nature”, where “Form of Motion” means “Eternal Motion” as the power of dynamics of different levels and varying degrees of self-sufficiency, and by “Special Nature”, gravitational and two other properties of matter, “tied” to the “Eternal Movement” and completely dependent on it. Carriers of key properties of a “Special Nature” have been established: “0”-DE particles and “3”-DM particles (UDM). The unity of their inherent “motionally-gravitational” properties and the peculiarity of the relationship between “motion” and “gravity” are revealed: the higher the intensity of “Eternal Motion”, the stronger the gravitational properties of matter are manifested (and vice versa). The relationship of “time” with the “vibration frequency” and the “mass” of photons with the “degree of bonding and deformation properties of the field” is shown. The maximum level of gravity has been determined, which allows Nature to successfully create the Universe: such a landmark is the proximity to the property of the Primary Source—the “pure graviton” of the OSP space, the most powerful “motionally-gravitational” particle of the Universe. The reasons for the emergence of such an identity of the gravitational properties of particles with the indicators of a “pure graviton” are established: for “0”-DE particles, this is the acquisition of the function of “freedom of movement”;for “3”-DM particles (UDM), the creation of a special structure—a “double field” (“Main” and “Small”). The presence in the “double field” of specific “tools” for the creation of the worlds of the Universe—gravitational “waves” gives rise to impulses (shocks) of varying intensity and shape. A list of functions performed by “waves” in the “Main” and “Small” fields has been compiled. The specific conditions for the formation of “UDM Streams”, their transformation into a “Vortex” and, under the influence of a powerful Initial Impulse (push), sending them to the “place” of the creation of galaxies, are shown. It is suggested that there is a “Cycle of Matter in Nature” in the closed structure of our Universe due to the “work” of “waves” and the functioning of special “factories” in the form of exotic space objects—Black holes. 展开更多
关键词 DE DM (UCM) Graviton Eternal motion Double Field of the Universe Motionally-Gravitational Particles Degree of Self-Sufficiency main Field Small Field Gravitational Waves Primary Impulse Flows UDM Vortex Time Massive Photons Clumps of DM Movement of Galaxies Factories of Black Holes Circulation of Matter in Nature
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指向社会责任的“海水稻渗透现象”主线式情境教学实践
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作者 仇敬运 《生物学教学》 北大核心 2025年第1期32-34,共3页
以“渗透现象”一节教学为例,在“海水稻”这一主线真情境中,学生经历“起境、承境、转境、合境”等情境的变化。在问题生成、任务驱动下,积极地进行了科学实验探索,培养批判性思维、创新思维等科学思维能力和社会责任意识。
关键词 社会责任 海水稻 主线式情境 渗透现象
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变化环境下西江干流水文情势演变及其驱动因素
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作者 李继清 刘佳利 +1 位作者 邓世浪 吴亮 《水资源保护》 北大核心 2025年第1期9-18,共10页
为掌握变化环境下西江干流水文情势演变特征及主要驱动因素,通过识别径流序列突变点将径流序列划分为天然时期和变化时期,采用基于水文改变指标的变化范围法定量探究各水文指标改变度,借助水文变异程度和水文情势变化法(DHRAM)评估整体... 为掌握变化环境下西江干流水文情势演变特征及主要驱动因素,通过识别径流序列突变点将径流序列划分为天然时期和变化时期,采用基于水文改变指标的变化范围法定量探究各水文指标改变度,借助水文变异程度和水文情势变化法(DHRAM)评估整体水文情势改变度,利用主成分分析法筛选最相关生态指标捕捉关键水文变量,并基于随机森林模型,结合残差分析法定量评估气候变化与人类活动对流域水文情势的影响。结果表明:西江干流4座水文站32个水文指标以中、低度改变为主,天峨、迁江、武宣、梧州站水文变异程度分别为64.70%、61.34%、51.70%、51.89%,基于DHRAM得到各站水文情势改变等级分别为3、3、2、3,综合判定4站整体水文情势改变度均为中度;中上游天峨、迁江站改变度比中下游武宣、梧州站高,应重点关注中上游生态保护;气候变化与人类活动均是西江干流水文情势变化的重要驱动因素,气候变化对天峨、迁江、武宣、梧州站水文情势变化的贡献率分别为25.65%、60.07%、50.29%、55.22%,气候变化对于西江流域中下游地区水文情势的影响大于上游地区。 展开更多
关键词 水文情势变化 IHA-RVA 驱动因素 随机森林模型 西江干流
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沙颍河干流河南段河道生态基流价值估算与分析
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作者 王国重 李中原 +4 位作者 杨丹 张武云 卢圆章 徐志国 邵全忠 《水土保持研究》 北大核心 2025年第1期203-208,共6页
[目的]为使人们认识河道生态基流的重要性,对其价值进行量化,以便推动生态基流保障补偿工作的开展。[方法]以沙颍河干流河南段为例,基于生态基流功能分析,将生态基流价值划分为维持河道连通、局地气候调节、泥沙输送、维系河滩湿地、生... [目的]为使人们认识河道生态基流的重要性,对其价值进行量化,以便推动生态基流保障补偿工作的开展。[方法]以沙颍河干流河南段为例,基于生态基流功能分析,将生态基流价值划分为维持河道连通、局地气候调节、泥沙输送、维系河滩湿地、生物多样性维护、净化水质、水产品生产、科研与文化娱乐等;河道气候调节价值的计算采用水体蒸发的吸热量与释放相同热量的标煤用量构建的估算模型,其他价值的测算则是基于资源环境经济学算法。[结果]2021年河南段气候调节价值为6.459亿元、泥沙输送价值5.056亿元、维持河滩湿地价值0.96亿元、生态多样性维护价值0.22亿元、水质净化价值10.28亿元、水产品生产价值10.092亿元、文化娱乐价值57.38亿元,则沙颍河干流2021年河南段生态基流总价值90.447亿元。[结论]各河段因所处位置、流域面积、区间长度等情况不同,生态基流价值差异较大,各河段生态基流价值占当地GDP比例均在1%以内,说明计算结果的合理性,也便于今后流域水土流失治理、生态保护与保障补偿工作的推进。 展开更多
关键词 生态基流价值 沙颍河干流 河南段 保障补偿
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职普融通主要模式的域外境鉴与中国建构
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作者 匡瑛 刘晓萍 《湖北民族大学学报(哲学社会科学版)》 北大核心 2025年第1期138-149,共12页
综观全球,职普融通是各国教育改革与发展中的普遍趋势。为了全面深入理解和分析各国职普融通做法,需立足各国国情,通过构建多维分析框架,梳理、总结、凝练各国职普融通的基本模式及其背后的内外部影响因素。研究得出,职普融通大致可以... 综观全球,职普融通是各国教育改革与发展中的普遍趋势。为了全面深入理解和分析各国职普融通做法,需立足各国国情,通过构建多维分析框架,梳理、总结、凝练各国职普融通的基本模式及其背后的内外部影响因素。研究得出,职普融通大致可以归纳为三种典型模式:德国和日本的职普互“通”、美国的职普互“融”和丹麦的职普互“通”互“融”兼顾。通过比较分析,发现职业启蒙教育是职普融通有效开展的前提,职普互“通”需要明确的路径设计与制度支持,职普互“融”需要在教育过程中实现两类教育的有机融合与循序渐进。基于此,立足中国特定的经济、社会、教育因素,从内外部因素出发分析了中国职普融通的背景以及面临的两大矛盾:专深型人才培养需求与晚分流的冲突;社会性功能和个体性功能难以兼顾。面向未来,中国的职普融通之路包括:一是需要理顺职普关系,立足协调发展,系统推进职普融通;二是搭建双向立交,完善纵横体系,服务个体生涯发展;三是打破部门利益,出台综合制度,健全落地运行保障。 展开更多
关键词 职普融通 主要模式 域外镜鉴 中国建构
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基于主路径分析的领域研究路径识别研究——以知识图谱为例
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作者 魏瑞斌 王伊丹 徐艳 《科技情报研究》 2025年第1期41-52,共12页
[目的/意义]引文网络的主路径分析可以对特定领域的重要文献进行识别,并能实现主流研究线索提取。文章旨在利用主路径分析方法,对知识图谱的研究路径进行分析,梳理其研究发展的脉络。[方法/过程]文章首先从Web of Science平台获取知识... [目的/意义]引文网络的主路径分析可以对特定领域的重要文献进行识别,并能实现主流研究线索提取。文章旨在利用主路径分析方法,对知识图谱的研究路径进行分析,梳理其研究发展的脉络。[方法/过程]文章首先从Web of Science平台获取知识图谱领域的研究论文,然后利用HistCite软件生成文献的直接引证网络,再将数据导入到Pajek中,生成该数据集的多条主路径,并结合主路径上论文的内容进行定性分析。[结果/结论]通过主路径分析,可以快速识别出知识图谱领域的一些主路径,如知识图谱的构建、知识图谱在推荐和问答等应用场景中的研究、知识图谱在制造业等特定应用领域的应用研究,折射出知识图谱技术的发展脉络和研究方向。综述性研究在知识图谱领域的发展中扮演了重要角色,为领域内的深入研究提供了基础和方向。 展开更多
关键词 主路径分析 引文网络 知识图谱 PAJEK 研究方法
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基于BIM技术的福建木结构文物建筑修缮保护研究——以华林寺大殿为例
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作者 季宏 莫智伟 王琼 《华中建筑》 2025年第1期64-69,共6页
以福州市华林寺大殿为研究对象,该文首先对2016年华林寺大殿的现状勘察病害与修缮措施进行了分类分析。其次,搭建和添加了更适宜福建官式木结构文物建筑保护修缮设计的BIM与参数。再次,实现了在BIM中呈现华林寺大殿现状病害以及分别生... 以福州市华林寺大殿为研究对象,该文首先对2016年华林寺大殿的现状勘察病害与修缮措施进行了分类分析。其次,搭建和添加了更适宜福建官式木结构文物建筑保护修缮设计的BIM与参数。再次,实现了在BIM中呈现华林寺大殿现状病害以及分别生成现状图纸和方案图纸的技术过程。最后,基于相关标准尝试建立福建官式木结构文物建筑信息模型修缮设计标准框架,可为福建地区建筑遗产保护修缮工程中建筑信息模型的建立、交付提供参考。将BIM技术运用到福建官式木结构文物建筑修缮是一次完美的尝试,为该地区的官式文物建筑保护提供了一定的技术支撑。 展开更多
关键词 华林寺大殿 BIM 病害 保护修缮 施工图纸 标准
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基于Ansys workbench煤矿风机主轴有限元分析
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作者 王磊 张军 王栋 《煤矿现代化》 2025年第2期13-17,共5页
煤矿风机在煤矿生产工作中起着重要的作用,风机主轴是风机的核心零件。针对风机主轴受到径向载荷和轴向载荷的影响是否会导致主轴损坏的问题,依据现实煤矿生产环境和条件,构建轴流式煤矿风机模型,对风机主轴进行静力学分析,根据主轴静... 煤矿风机在煤矿生产工作中起着重要的作用,风机主轴是风机的核心零件。针对风机主轴受到径向载荷和轴向载荷的影响是否会导致主轴损坏的问题,依据现实煤矿生产环境和条件,构建轴流式煤矿风机模型,对风机主轴进行静力学分析,根据主轴静力学分析中出现的主轴应力集中现象提出解决方案。对风机主轴进行优化设计,重新进行静力学分析,消除应力集中现象。采用模态分析法对风机主轴的强度性能和刚度性能进行检测,最后通过搭建试验平台对仿真结果进行验证。结果表明,当风机机主轴径向与轴向同时增加载荷时,风机主轴在工作过程中可安全可靠的运行。 展开更多
关键词 煤矿风机 主轴 静力学分析 模态分析 优化设计
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基于变异系数法的沙颍河上游干流生态基流价值变化研究
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作者 王国重 李中原 +3 位作者 卢圆章 李永丽 杨丹 张继宇 《水力发电》 CAS 2025年第1期11-15,共5页
为了辨识生态基流价值变化规律,以沙颍河上游干流告成段、化行段、黄桥段2008年~2021年降水、蒸发、流量、人均用水量、人均GDP、水质达标率数据,建立影响生态基流因子体系,根据变异系数法和2021年生态基流价值,研究河段生态基流价值年... 为了辨识生态基流价值变化规律,以沙颍河上游干流告成段、化行段、黄桥段2008年~2021年降水、蒸发、流量、人均用水量、人均GDP、水质达标率数据,建立影响生态基流因子体系,根据变异系数法和2021年生态基流价值,研究河段生态基流价值年际变化。研究表明:告成段生态基流价值在0.483亿~4.726亿元波动、化行段在10.106亿~79.954亿元变化、黄桥段变化范围是7.201亿~46.431亿元;告成段、黄桥段水质因子所占权重最大,其次是流量、降水量因子;化行段因水质较优,流量因子所占权重最大,水质、降水量因子次之;经济、蒸发量、用水量因子在各河段的权重均较小,对生态基流价值的影响不大。河段年均流量与降水量排序为黄桥段>化行段>告成段,但生态基流价值排序为化行段>黄桥段>告成段,说明生态基流价值首先取决于水质,其次是流量与降水量。 展开更多
关键词 生态基流 价值 变异系数法 权重 变化 沙颍河上游干流
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Construction of Anti-breaking Models of the Main Veins of Flue-cured Tobacco Leaves and Principal Component Analysis 被引量:4
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作者 王宝玉 孙婷婷 +3 位作者 章国顺 张蜀香 阮龙 张云华 《Agricultural Science & Technology》 CAS 2011年第11期1615-1616,1656,共3页
[Objective] This study aimed to explore the related mechanisms of the breaking of flue-cured tobacco leaves. [Method] Anti-breaking models of the main veins of flue-cured tobacco leaves were constructed for principal ... [Objective] This study aimed to explore the related mechanisms of the breaking of flue-cured tobacco leaves. [Method] Anti-breaking models of the main veins of flue-cured tobacco leaves were constructed for principal component analysis on the anti-breaking index, leaf traits and cellulose contents. [Result] The results showed that the growth traits had certain relevance with the cellulose contents while the leaf weight assumed a significant negative correlation with the anti-breaking index, indicating that the heavier the leaf weight was, the weaker the anti-breaking capacity of flue-cured tobacco would be; the cross-sectional area of main veins and the cellulose contents had shown a positive correlation with the anti-breaking index, indicating that the thicker the main vein of flue-cured tobacco was, the higher the cellulose contents would be, and the stronger the anti-breaking capacity of flue-cured tobacco leaves would be. [Conclusion] This study provided theoretical basis and reference to improve tobacco production and enhance the quality of flue-cured tobacco. 展开更多
关键词 Flue-cured tobacco main vein Anti-breaking index Principal component analysis
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Analysis on the Combining Ability and Heritability of Main Agronomic Traits of Hybrid Glutinous Sorghum 被引量:1
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作者 倪先林 赵甘霖 +3 位作者 刘天朋 胡炯凌 陈国民 丁国祥 《Agricultural Science & Technology》 CAS 2012年第10期2104-2109,共6页
Using 3 sterile lines and 12 restorer of glutinous sorghum as experimental materials,36 hybrid combinations(3×12 NCⅡ) were designed to analyze the combining ability and heritability of six main agronomic trait... Using 3 sterile lines and 12 restorer of glutinous sorghum as experimental materials,36 hybrid combinations(3×12 NCⅡ) were designed to analyze the combining ability and heritability of six main agronomic traits,including plant height,panicle length,growth period,1 000-grain weight,per panicle grains and per panicle grain weight.The results showed that except per panicle grain number all other five agronomic traits have remarkable or extremely remarkable general combining ability and specific combining ability.Six agronomic traits were found to be control by additive genetic effect.Most of these agronomic traits are more easily influenced by restorers than sterile lines,suggesting that more attention should be paid to select restores in hybrid glutinous sorghum breeding.The narrow-sense heritability of these agronomic traits were in order growth period plant height per panicle grain weight panicle length 1 000-grain weight per panicle grains. 展开更多
关键词 Hybrid glutinous sorghum main agronomic traits Combining ability HERITABILITY
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基于SSR标记的青海蚕豆品种亲缘关系分析与指纹图谱构建
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作者 郑栋 周仙莉 +3 位作者 滕长才 侯万伟 张红岩 刘玉皎 《作物学报》 CAS 北大核心 2025年第1期79-90,共12页
为明确青海蚕豆育成品种、高代品系和骨干亲本的群体结构与亲缘关系,本研究利用46对多态性和稳定性好、重复性高的SSR引物对36个青海蚕豆主栽品种(品系)进行群体遗传学分析并构建了指纹图谱。结果表明,通过毛细管电泳检测,在46对引物中... 为明确青海蚕豆育成品种、高代品系和骨干亲本的群体结构与亲缘关系,本研究利用46对多态性和稳定性好、重复性高的SSR引物对36个青海蚕豆主栽品种(品系)进行群体遗传学分析并构建了指纹图谱。结果表明,通过毛细管电泳检测,在46对引物中检测到262个等位位点,各引物检测的多态性等位位点数(Na)为2~15,平均等位位点数为5.696个,平均每个位点检测到的有效等位基因数为2.988个,范围为1.180~9.257;Shannon指数的变化范围为0.287~2.444,均值为1.210;多态性信息含量(polymorphism information content, PIC)值变化范围为0.141~0.883,均值为0.553,揭示了青海蚕豆品种丰富的遗传多样性。系统聚类将36份材料划分为4个亚群,第Ⅰ、Ⅱ、Ⅲ、Ⅳ亚群分别包括24、4、7、1份材料;群体结构与主坐标分析将材料划分为2个亚群,亚群Ⅰ和亚群Ⅱ分别包括17和19份材料,与聚类分类结果有一定程度的交叉重合,厘清了青海蚕豆主栽品种的群体遗传结构与亲缘关系。在此基础上,筛选出4对核心引物,构建了36份材料的指纹图谱,并将相关信息储存在二维码中。青海蚕豆主栽品种指纹图谱的构建不仅为青海蚕豆品种鉴定提供了有效工具,也为今后青海蚕豆品种亲本选配和新品种权保护提供了技术支撑。 展开更多
关键词 蚕豆 青海 主栽品种 SSR标记 亲缘关系 指纹图谱
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