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Gradual Clamping Reduced Ischemia-Reperfusion Injury in an Isolated Rat Heart Model 被引量:2
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作者 Hongbin Feng Hongli Wang +2 位作者 Yang Zhao Zhinan Zheng Sanqing Jin 《World Journal of Cardiovascular Surgery》 2016年第6期79-86,共8页
Objectives: We hypothesized that the organisms and their organs or tissues could adapt themselves to the gradual changes of environment for surviving or reducing damage. This study explored whether gradual clamping (G... Objectives: We hypothesized that the organisms and their organs or tissues could adapt themselves to the gradual changes of environment for surviving or reducing damage. This study explored whether gradual clamping (GC) could reduce myocardial ischemia-reperfusion (IR) injury in rat heart. Methods: Twelve rats were randomized to IR group and GC group, then the hearts were isolated and perfused with Langendorff apparatus. Before cardioplegia, the perfusion was stopped abruptly in IR group while slowly with 5-minute in GC group. The hearts were subjected to 30-minute ischemia and 60-minute reperfusion. The left ventricular develop pressure (LVDP) and systolic pressure (LVSP), the maximal rate of the increase and decrease of left ventricular pressure (+dp/dt<sub>max</sub>, ﹣dp/dt<sub>max</sub>) were measured by polygraph system at different time points. The recovery of the variables was expressed as the ratio of these values at individual time point after reperfusion to the baseline respectively. Results: The recovery of LVDP after reperfusion was better than that in IR group (P = 0.034). No significant difference in the recovery of LVSP, +dp/dtmax and ﹣dp/dt<sub>max</sub> between groups was observed. Conclusions: Gradual clamping could improve the recovery of LVDP after IR, suggesting that gradual clamping could reduce myocardial IR injury. 展开更多
关键词 gradual Clamping Ischemia-Reperfusion Injury gradual Adaptation Rat Heart Model
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英语短语动词的三要素——以away组成的含gradually之义的短语动词为例
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作者 赵静云 《安徽农业大学学报(社会科学版)》 2003年第6期124-128,共5页
从语义的角度来对短语动词进行系统地认知是一种科学的新理念、新方法。以短语动词中的副词或介词为主线来进行纵向的组群亦是切实可行的一种好方法。然后在横向上辨析相关的同义的短语。以三者的有机结合所形成的复合思维来加以认知则... 从语义的角度来对短语动词进行系统地认知是一种科学的新理念、新方法。以短语动词中的副词或介词为主线来进行纵向的组群亦是切实可行的一种好方法。然后在横向上辨析相关的同义的短语。以三者的有机结合所形成的复合思维来加以认知则更具特色。由away组成的短语动词可表数个意义。含“gradually”之义时,所表意义为动状关系。 展开更多
关键词 英语 短语动词 三要素 away gradually 语义认知 纵向组群 动状关系
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Gradual solution heat treatment of AlSiCuMg cast alloys 被引量:13
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作者 WANG Guiqing , BIAN Xiufang ,and ZHANG Junyan1) The Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jinan 250061, China2) Department of Material Science and Technology, Shandong Architectural Engineering Institute, Jinan 250014, China 《Rare Metals》 SCIE EI CAS CSCD 2003年第4期304-308,共5页
The microstructure characteristics of AlSiCuMg cast alloys were studied withdifferent Cu content and the gradual solution treatment by DSC, SEM, TEM and mechanical method. Themelting point of alpha (Al) + Si decreases... The microstructure characteristics of AlSiCuMg cast alloys were studied withdifferent Cu content and the gradual solution treatment by DSC, SEM, TEM and mechanical method. Themelting point of alpha (Al) + Si decreases and polynary eutectic phases with low melting point formwith increase of Cu content. Gradual solution treatment includes two steps: solution treating nearthe melting point of polynary eutectic phase to take it dissolve first, and then increasing solutiontemperature to take the remainder copper intermetallics dissolved into alpha (Al). Grain boundariesmelting can be avoided by gradual solution treatment, even the maximum solution temperature isabove final solidification point, and the age hardening response increases correspondingly 展开更多
关键词 aluminum alloy gradual solution heat treatment differential scanningcalorimetry (DSC) polynary eutectic phase
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Improved Plasticity and Cold-rolling Workability of Fe–6.5wt%Si Alloy by Warm-rolling with Gradually Decreasing Temperature 被引量:4
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作者 Yuanke Mo Zhihao Zhang +1 位作者 Hongjiang Pan Jianxin Xie 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2016年第5期477-484,共8页
The effects of warm-rolling process on the microstructure, ordering, mechanical properties and cold- rolling workability of Fe-6.Swt%Si alloy were investigated, where three processes of warm-rolling with the same tota... The effects of warm-rolling process on the microstructure, ordering, mechanical properties and cold- rolling workability of Fe-6.Swt%Si alloy were investigated, where three processes of warm-rolling with the same total reduction of 93% were used, including (1) 500 ℃/12 passes/total reduction of 93%, (2) 500 ℃13 passes/total reduction of 50% + 400 ℃19 passes/total reduction of 86%, and (3) 500 ℃13 passes/total reduction of 50% + 400 ℃15 passes/total reduction of 60% + 300 ℃14 passes/total reduction of 64%. The results show that compared with process (1) warm-rolling with constant temperature of 500 ℃, process (2) and process (3) warm-rolling with gradually decreasing temperature can significantly improve the room temperature plasticity and cold-rolling workability of the Fe-6.5wt%Si alloy. For example, the three point bending fracture deflections are increased by 54.5% and 81.8% for processes (2) and (3), respectively, and the maximum reductions of single pass cold-rolling without edge crack are increased from 50% of process (1) to 55% of process (2) and 62% of process (3), respectively. The plasticity improvement of the Fe- 6.5wt%Si alloy can be attributed to both reductions of surface oxidation degree and order degree of the alloy by warm-rolling with gradually decreasing temperature. 展开更多
关键词 Fe–6.5wt%Si alloy Warm-rolling gradually decreasing temperature Ordering Mechanical property
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ANALYSIS MODEL ON GRADUAL CHANGE PRINCIPLE OF EFFECT ZONES OF LAYER FACE FOR ROLLED CONTROL CONCRETE DAM 被引量:1
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作者 顾冲时 宋敬衖 方海挺 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第11期1523-1529,共7页
The effect zones of layer face for RCC (rolled control concrete) dam have gradual change characteristics. Based on the analysis thought of complex material, a model was built to analyze above principle of RCC dam by... The effect zones of layer face for RCC (rolled control concrete) dam have gradual change characteristics. Based on the analysis thought of complex material, a model was built to analyze above principle of RCC dam by use of series-wound and shunt-wound connection. Some methods were proposed to determine the instantaneous Young's modulus, delayed Young's modulus and viscosity coefficient of effect zones of layer face. Above models and methods were used to mine the principle of gradual change of key calculation parameters which can response the characteristics of effect zones. The principle of gradual change was described. A model was established to analyze the threedimensional viscoelastic problem of RCC dam. Above programs were developed. The examples show that the proposed models and methods to determine the key calculation parameters of effect zones can reflect the status of RCC dam accurately. 展开更多
关键词 (rolled control concrete dam) effect zones calculation parameter principle of gradual change viscoelastic model
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A gradually descent method for discrete global optimization 被引量:1
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作者 杨永建 张连生 《Journal of Shanghai University(English Edition)》 CAS 2007年第1期39-44,共6页
In this paper, a new method named as the gradually descent method was proposed to solve the discrete global optimization problem. With the aid of an auxiliary function, this method enables to convert the problem of fi... In this paper, a new method named as the gradually descent method was proposed to solve the discrete global optimization problem. With the aid of an auxiliary function, this method enables to convert the problem of finding one discrete minimizer of the objective function f to that of finding another at each cycle. The auxiliary function can ensure that a point, except a prescribed point, is not its integer stationary point if the value of objective function at the point is greater than the scalar which is chosen properly. This property leads to a better minimizer of f found more easily by some classical local search methods. The computational results show that this algorithm is quite efficient and reliable for solving nonlinear integer programming problems. 展开更多
关键词 gradually descent method nonlinear integer programming integer programming ALGORITHM
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The gradual subduction-collision evolution model of Proto-South China Sea and its control on oil and gas 被引量:1
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作者 Xiaojun Xie Wu Tang +5 位作者 Gongcheng Zhang Zhigang Zhao Shuang Song Shixiang Liu Yibo Wang Jia Guo 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第3期123-137,共15页
This study involved outcrop,drilling,seismic,gravity,and magnetic data to systematically document the geological records of the subduction process of Proto-South China Sea(PSCS)and establish its evolution model.The re... This study involved outcrop,drilling,seismic,gravity,and magnetic data to systematically document the geological records of the subduction process of Proto-South China Sea(PSCS)and establish its evolution model.The results indicate that a series of arc-shaped ophiolite belts and calcalkaline magmatic rocks are developed in northern Borneo,both of which have the characteristics of gradually changing younger from west to east,and are direct signs of subduction and collision of PSCS.At the same time,the subduction of PSCS led to the formation of three accretion zones from the south to the north in Borneo,the Kuching belt,Sibu belt,and Miri belt.The sedimentary formation of northern Borneo is characterized by a three-layer structure,with the oceanic basement at the bottom,overlying the deep-sea flysch deposits of the Rajang–Crocker group,and the molasse sedimentary sequence that is dominated by river-delta and shallow marine facies at the top,recording the whole subduction–collision–orogeny process of PSCS.Further,seismic reflection and tomography also confirmed the subduction and collision of PSCS.Based on the geological records of the subduction and collision of PSCS,combined with the comprehensive analysis of segmented expansion and key tectonic events in the South China Sea,we establish the“gradual”subduction-collision evolution model of PSCS.During the late Eocene to middle Miocene,the Zengmu,Nansha,and Liyue–Palawan blocks were separated by West Baram Line and Balabac Fault,which collided with the Borneo block and Kagayan Ridge successively from the west to the east,forming several foreland basin systems,and PSCS subducted and closed from the west to the east.The subduction and extinction of PSCS controlled the oil and gas distribution pattern of southern South China Sea(SSCS)mainly in three aspects.First,the“gradual”closure process of PSCS led to the continuous development of many large deltas in SSCS.Second,the deltas formed during the subduction–collision of PSCS controlled the development of source rocks in the basins of SSCS.Macroscopically,the distribution and scale of deltas controlled the distribution and scale of source rocks,forming two types of source rocks,namely,coal measures and terrestrial marine facies.Microscopically,the difference of terrestrial higher plants carried by the delta controlled the proportion of macerals of source rocks.Third,the difference of source rocks mainly controlled the distribution pattern of oil and gas in SSCS.Meanwhile,the difference in the scale of source rocks mainly controlled the difference in the amount of oil and gas discoveries,resulting in a huge amount of oil and gas discoveries in the basin of SSCS.Meanwhile,the difference of macerals of source rocks mainly controlled the difference of oil and gas generation,forming the oil and gas distribution pattern of“nearshore oil and far-shore gas”. 展开更多
关键词 Proto-South China Sea gradual subduction-collision evolution model oil and gas distribution southern South China Sea BORNEO
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Gradual Band Energy to Passivate the Window Layer in Solar Cells
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作者 A. Amine M. Bouabdellaoui +2 位作者 K. Zaz Y. Mir M. Zazoui 《Smart Grid and Renewable Energy》 2017年第1期46-51,共6页
The passivation layers at the front of the cell are often referred as to the window layer because it must be transparent so as the solar cell has a high efficiency. In this work, numerical simulation has been proposed... The passivation layers at the front of the cell are often referred as to the window layer because it must be transparent so as the solar cell has a high efficiency. In this work, numerical simulation has been proposed to study the effect of the AlGaAs gradual and normal windows on the cell sensitivity to the electron irradiation so as to passivate the solar cell. To expect the effect of gradual window layers, the J-V and P-V characteristics are confirmed better energy conversion performance of the illuminated solar cells after irradiation. The short circuit current Jsc and the open circuit voltage Voc are evaluated for different electron irradiation fluencies. The results show how the gradual window layer improves resistance to electron irradiation through its own parameters. 展开更多
关键词 gradual WINDOW ELECTRIC Field DEGRADATION SOLAR Cell
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Gradual Bedside Reduction of Gastroschisis in a Resource Constrained Setting: Preliminary Results from 32 Cases
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作者 Nyanit Bob Dorcas Ntsobé Eric Tobie +9 位作者 Ndikontar Raymond Kouna Tsala Irène Nadine Ndongo René Bougoue Takou Horline Vougmo Clémence Kana Serges Paule Ngayap Guy Owono Etoundi Paul Essiene Agnès Steyaert Henri 《Open Journal of Pediatrics》 2023年第5期669-675,共7页
Introduction: Gastroschisis is one of the neonatal pathologies with bad prognosis in developing countries due to a lack of equipment. We aim to report one way of managing this malformation that could be practised ever... Introduction: Gastroschisis is one of the neonatal pathologies with bad prognosis in developing countries due to a lack of equipment. We aim to report one way of managing this malformation that could be practised everywhere, constituting an alternative approach to surgery in poor areas. Patients and Methods: This observational and descriptive study included newborn babies with gastroschisis who underwent gradual bedside reduction at the Paediatric Surgery Department of the Yaounde Central Hospital. Results: Our cohort was constituted by 32 newborn babies with a mean age of 18.12 hours on admission. The Lefort type 2 was the most frequent in 81.25% of cases. The mean time for oral feeding after complete reduction was 17.4 days and the duration of hospital stay was 24.91 days. Survival rates were at 40.63%, with a residual hernia after healing in 38.46% of cases. Conclusion: Despite the high rate of mortality, gradual reduction of gastroschisis at the bedside seems to be an opportunity for resource constrained areas and can be an alternative solution to surgery. 展开更多
关键词 GASTROSCHISIS Lefort Type 2 gradual Reduction Limited Resources
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China's Science Gradually Strengthened
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作者 Shangguan Yun 《China's Foreign Trade》 1995年第11期9-9,共1页
In order to ensure the steady development of our science, the Chinese government has continuously increased input in the last ten years. Information from the State Statistics Bureau shows that by the end of 1994, the ... In order to ensure the steady development of our science, the Chinese government has continuously increased input in the last ten years. Information from the State Statistics Bureau shows that by the end of 1994, the national institutions and enterprises boasted 18.659 million technical experts, 4.3 times the number in 1978, or 1258 technical experts every ten thousand people, redoubling that of 1978. The whole country has 5860 independent scientific research and development (R & D) institutions, 展开更多
关键词 HIGH China’s Science gradually Strengthened
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Effects of Gradual Water Deficit Stress on Phenological and Morphological Traits in Chickpea (Cicer arietinum L.)
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作者 N. Niari Khamssi K. Ghassemi Golezani +1 位作者 S. Zehtab A. Najaphy 《Journal of Agricultural Science and Technology》 2010年第5期95-100,共6页
The aims of this study were to investigate the effect of gradual water deficit stress on some phonological and morphological traits and grain yield of desi and kabuli chickpea cultivars. This study was carried out in ... The aims of this study were to investigate the effect of gradual water deficit stress on some phonological and morphological traits and grain yield of desi and kabuli chickpea cultivars. This study was carried out in 2007 and 2008, to evaluate responses of three chickpea cultivars (Hashem and Arman from kabuli and Pirooz from desi type) under well watering (I1: 70mm evaporation from class A pan), gradual water deficit (12 and 13: 70→90→ 110→130 and 70→100→130mm evaporation from class A pan, respectively) and severe water stress (14: 130mm evaporation from class A pan). Result showed that days to flowering and plant height were decreased, as water limitation increased. This reduction was significant under gradual water stress (I2 and I3) and Severe water deficit (I4), compared with control (I1). There were no significant differences in grain filling period and grain yield among I~, I2 and I3 irrigation treatments. No significant differences in days to physiologic maturity and number of sub branches were recorded among irrigation treatments. Interactions of year×cultivar for days to physiologic maturity, grain filling period and grain yield (P≤0.01) and for days to flowering and plant height (P≤0.05) were significant. The superiority of Arman in producing comparatively greater grain yield could be attributed to higher grain filling period of this cultivar in both years. 展开更多
关键词 CHICKPEA gradual water deficit grain filling period grain yield physiologic maturity.
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On the Gradualness by the Narrative Ambiguity in The Sound and The Fury 被引量:1
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作者 Tian Ping Hong Zengliu 《学术界》 CSSCI 北大核心 2012年第11期253-262,共10页
How to disambiguate the four narrators'narratives is the critical step to understand the whole work of The Sound and The Fury. With the gradualness produced by the ambiguous narrators'narration of juxtapositio... How to disambiguate the four narrators'narratives is the critical step to understand the whole work of The Sound and The Fury. With the gradualness produced by the ambiguous narrators'narration of juxtaposition of modern and traditional narration,another synchronized gradualness of Caddy is discovered,too. On the basis of deconstruction and psycho - analyses,rich and deep significance is illustrated by elucidation of narrative gradualness,as a new way to disambiguate the narrators'narration. 展开更多
关键词 歧义 骚动 渐进性
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Verification on Gradual Escalation Phenomenon of Violation Behavior Using an Experimental Paradigm for Risk Diversification
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作者 Atsuo Murata 《Psychology Research》 2015年第3期197-204,共8页
关键词 违法违规行为 风险评估 分散 验证 不道德行为 冒险行为 安全规则 实验
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渐进性制度变迁理论视角下我国公共服务政策的变迁逻辑 被引量:2
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作者 王欢明 朱欢 徐佳 《大连理工大学学报(社会科学版)》 北大核心 2025年第3期99-109,共11页
21世纪以来,我国公共服务在各类政策的引领和推动下实现了快速发展。尽管有研究阐释了我国公共服务及其政策的发展历程,但是对于采用了怎样的政策变迁模式并没有定论。厘清政策变迁的模式对于解答发展之谜、化解发展困局、推动公共服务... 21世纪以来,我国公共服务在各类政策的引领和推动下实现了快速发展。尽管有研究阐释了我国公共服务及其政策的发展历程,但是对于采用了怎样的政策变迁模式并没有定论。厘清政策变迁的模式对于解答发展之谜、化解发展困局、推动公共服务体系建设迈上新台阶具有重要价值。依据渐进性制度变迁理论归纳得出漂移、转换、层叠和更替4种渐进性政策变迁模式的判定方式。从2001—2022年,“人人享有——人人平等享有——人人满意”构成了我国公共服务政策的主轴,通过对政策目标、主体和工具3项内容及其演化过程进行分析,研究发现该领域的政策变迁模式以层叠为主,通过层叠,公共服务政策的目标、主体和工具的内容不断丰富,反映了公共服务的边界不断扩大的特点。此外,漂移、转换和更替等模式也在此过程中相互交织,与层叠共同塑造了如今的公共服务供给现状。 展开更多
关键词 公共服务 渐进性政策变迁 政策层叠
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数据要素和传统要素协同配置与企业新质生产力 被引量:2
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作者 韩永彩 程丽雯 钟昌标 《工业技术经济》 北大核心 2025年第4期80-89,共10页
新质生产力强调生产要素和生产资料的有机协同,以数据要素为“催化剂”,实现新旧生产要素的创新性配置。本文利用2015~2023年中国A股上市公司数据,探究数据要素与传统要素协同促进新质生产力的机制。结果显示:数据-传统要素协同不仅具... 新质生产力强调生产要素和生产资料的有机协同,以数据要素为“催化剂”,实现新旧生产要素的创新性配置。本文利用2015~2023年中国A股上市公司数据,探究数据要素与传统要素协同促进新质生产力的机制。结果显示:数据-传统要素协同不仅具有新质生产力提升的直接效应,还具有以底层基础效能提升下的“量变”递进到上层建筑结构优化下的“质变”的间接路径;数据-劳动力协同对新质生产力的提升效应强于数据-资本协同;高新技术企业和非重污染企业提升效应更强。此结果纠正了企业发展新质生产力“一味求新”的误区,引导企业遵循比较优势,打造“以传统要素创造新型要素、以新型要素改造传统要素”的要素协同机制,为循序渐进发展新质生产力提供新思路。 展开更多
关键词 新质生产力 数据要素 资本要素 劳动力要素 协同 比较优势 渐进式发展 量变到质变
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不同多孔介质布置下低浓度甲烷燃烧特性
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作者 张建国 翟成 +4 位作者 张国川 曹运齐 刘方 仝艳军 苏童 《科学技术与工程》 北大核心 2025年第16期6752-6759,共8页
为了解决传统直燃式多孔介质燃烧器存在火焰稳定性差、燃烧效率低和贫极限高的问题,通过构建5种排布方式的多孔介质燃烧器用于低浓度甲烷(low-concentration methane,LCM)燃烧实验,研究不同多孔介质排布方式、当量比和流量对LCM燃烧特... 为了解决传统直燃式多孔介质燃烧器存在火焰稳定性差、燃烧效率低和贫极限高的问题,通过构建5种排布方式的多孔介质燃烧器用于低浓度甲烷(low-concentration methane,LCM)燃烧实验,研究不同多孔介质排布方式、当量比和流量对LCM燃烧特性的影响,并分析贫燃工况下的CH4转化率、污染物排放和烟气温度。结果表明:渐变E型多孔介质燃烧器具有最佳的LCM燃烧适应性,可部分弥补LCM燃烧过程中的界面温度扰动,提高LCM燃烧稳定性。在当量比0.39、流量50 L/min的条件下,LCM驻定燃烧时间超过140 min,火焰位置始终维持在60 mm处。LCM在E型燃烧器中燃烧的CH4转化率为99.99%,CO和NOx排放分别为531×10^(-6)和23×10^(-6),产生平均温度588℃以上的高品质烟气可用于工业生产。研究成果为提高煤矿低浓度瓦斯利用效率、降低甲烷排放提供重要参考。 展开更多
关键词 多孔介质燃烧 低浓度甲烷 渐变排布 燃烧特性 可燃极限
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切除肩胛间褐色脂肪组织对雌性黑线仓鼠免疫功能的影响
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作者 徐德立 王逸 +1 位作者 张学英 王德华 《兽类学报》 北大核心 2025年第4期457-467,共11页
为了解产热对动物免疫能力的影响,通过肩胛间褐色脂肪组织(interscapular brown adipose tissue,IBAT)切除术和低温处理,将雌性黑线仓鼠(Cricetulus barabensis)随机分为常温假切组(warm BAT sham‑removed group,WS,n=5)、低温假切组(co... 为了解产热对动物免疫能力的影响,通过肩胛间褐色脂肪组织(interscapular brown adipose tissue,IBAT)切除术和低温处理,将雌性黑线仓鼠(Cricetulus barabensis)随机分为常温假切组(warm BAT sham‑removed group,WS,n=5)、低温假切组(cold BAT sham‑removed group,CS,n=7)和低温切除组(cold BAT removed group,CR,n=8),比较了产热和免疫器官大小及血液指标和免疫功能的差异。结果发现,切除IBAT或逐渐降温均不影响雌性黑线仓鼠的体质量和身体成分,但低温导致总脂肪质量下降。切除IBAT不影响肝脏、脾脏和胸腺等器官的鲜质量,提示器官水平产热和免疫之间无权衡关系,但逐渐降温增加了小肠鲜质量及长度、结肠鲜质量、总消化道长,暗示为满足低温下的高能量需求,其加工食物的能力和消化能力均有所增强。切除IBAT或逐渐降温不影响植物血球凝集素反应峰值,以及白细胞、淋巴细胞、中间粒细胞和中性粒细胞的数量。低温或切除IBAT不影响雌性黑线仓鼠的免疫功能。 展开更多
关键词 黑线仓鼠 褐色脂肪组织切除 免疫功能 血液学 逐渐降温
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退市制度与公司债务融资成本——基于中国渐进式退市制度的准自然实验 被引量:1
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作者 孙建军 韩滋 祖楠楠 《海南大学学报(人文社会科学版)》 2025年第2期58-66,共9页
以中国上市公司渐进式退市制度改革为准自然实验,考察了渐进式退市制度对公司债务融资成本效应的影响。选取2000—2021年沪深两市主板上市公司为样本,采用多期双重差分方法,研究结果表明,渐进的退市制度经济与统计上显著地降低公司债务... 以中国上市公司渐进式退市制度改革为准自然实验,考察了渐进式退市制度对公司债务融资成本效应的影响。选取2000—2021年沪深两市主板上市公司为样本,采用多期双重差分方法,研究结果表明,渐进的退市制度经济与统计上显著地降低公司债务融资成本。机制分析表明,渐进的退市制度通过公司会计稳健性的提高和公司代理成本的降低这两个途径减少公司债务融资成本。异质性分析表明,渐进的退市制度降低公司债务融资成本的效应在非国有公司、独立董事比例高或外部审计质量低的公司更显著。本文结论不仅拓展了外部监管对公司治理效应的研究,还为中国上市公司监管政策有效性的评估提供参考。 展开更多
关键词 退市制度 债务融资成本 渐进 多期双重差分模型
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云化架构下的5G核心网灰度升级策略应用研究 被引量:1
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作者 郭威 欣娜 +2 位作者 常艳生 秦庆伟 张泽阳 《邮电设计技术》 2025年第4期19-24,共6页
网络技术的迭代演进推动移动核心网全面采用虚拟化技术的云化架构部署。基于商用5GC网络,探索高可靠、高安全的灰度升级策略在通信网络领域中运用的可行性,通过网络运营新技术的创新应用,提升网络运营效率,增强网络运营安全。
关键词 灰度升级 灰度比例 网络升级
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基于不同算法渐变式液压缓冲器的优化研究
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作者 尤小梅 侯晓冬 《组合机床与自动化加工技术》 北大核心 2025年第6期176-181,共6页
以履带车辆渐变节流式液压缓冲器为研究对象,为了提高其缓冲性能,建立缓冲过程数学模型,利用MATLAB数值仿真分析了结构参数对缓冲特性的影响。以最大缓冲效率为优化目标,以高压腔半径、阻尼孔半径、长度及节流杆初始半径为变量建立了缓... 以履带车辆渐变节流式液压缓冲器为研究对象,为了提高其缓冲性能,建立缓冲过程数学模型,利用MATLAB数值仿真分析了结构参数对缓冲特性的影响。以最大缓冲效率为优化目标,以高压腔半径、阻尼孔半径、长度及节流杆初始半径为变量建立了缓冲器优化模型,分别采用蚁群算法、萤火虫优化算法及麻雀搜索算法进行优化。结果表明,相较于原有结构的渐变节流式液压缓冲器,在3种算法优化后,缓冲效率得到提升,缓冲力及压强差的峰值显著下降,其中麻雀搜索算法与其他算法相比,在缓冲器的组合优化中收敛速度更快,优化效果也更为理想。 展开更多
关键词 渐变节流式液压缓冲器 数值仿真 缓冲效率 组合优化 优化算法
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