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黄土高原典型流域水蚀因子多重分形特征
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作者 李莹莹 魏舟 +1 位作者 童亚文 张青峰 《水土保持研究》 CSCD 2024年第2期122-129,共8页
[目的]探索高程、坡度、土地利用、植被覆盖度等水蚀因子的空间内部多重分形特征,进而深刻认识黄土高原水蚀机理。[方法]分别以黄土高原沟壑区和黄土丘陵沟壑区的两个典型流域(长武县王东沟流域与淳化县泥河沟流域,米脂县泉家沟流域与... [目的]探索高程、坡度、土地利用、植被覆盖度等水蚀因子的空间内部多重分形特征,进而深刻认识黄土高原水蚀机理。[方法]分别以黄土高原沟壑区和黄土丘陵沟壑区的两个典型流域(长武县王东沟流域与淳化县泥河沟流域,米脂县泉家沟流域与安塞县纸坊沟流域)为例,利用多重分形方法计算分析了水蚀因子的多重分形谱及其主要参数,探讨了水蚀因子多重分形特征。[结果]地貌相对起伏最大和土地利用空间不均匀程度最高的是王东沟流域,其坡度与土地利用的奇异指数Δα值分别是0.817,0.310,而植被覆盖区域差异最大的是泉家沟流域,其植被覆盖的Δα=1.309;黄土丘陵沟壑区高程的Δf(α)<0,黄土高原沟壑区坡度的Δα与Δf(α)皆大于丘陵沟壑区,即丘陵沟壑区的相对起伏更大,地貌表面更尖锐,土地利用破碎化更严重,植被覆盖区域间复杂程度高。[结论]王东沟流域的地貌相对起伏程度和土地利用破碎化更大,泉家沟流域的植被覆盖复杂程度最高,与实际情况相符,即在区域开展水蚀因子量化进行多重分形特征分析是可行的。 展开更多
关键词 水蚀因子 多重分形 高原沟壑区 丘陵沟壑区 小流域
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Controllable step-flow growth of GaN on patterned freestanding substrate
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作者 Peng Wu Jianping Liu +7 位作者 Lei Hu Xiaoyu Ren Aiqin Tian wei zhou Fan Zhang Xuan Li Masao Ikeda Hui Yang 《Journal of Semiconductors》 EI CAS CSCD 2024年第2期46-50,共5页
A new kind of step-flow growth mode is proposed,which adopts sidewall as step source on patterned GaN substrate.The terrace width of steps originated from the sidewall was found to change with the growth temperature a... A new kind of step-flow growth mode is proposed,which adopts sidewall as step source on patterned GaN substrate.The terrace width of steps originated from the sidewall was found to change with the growth temperature and ammonia flux.The growth mechanism is explained and simulated based on step motion model.This work helps better understand the behaviors of step advancement and puts forward a method of precisely modulating atomic steps. 展开更多
关键词 step-flow growth GAN terrace width step motion
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Molecular mechanism of Xuebijing in treating pyogenic liver abscess complicated with sepsis
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作者 wei zhou Maiying Fan +3 位作者 Xiang Li Fang Yu En zhou Xiaotong Han 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2024年第1期35-40,共6页
BACKGROUND:Xuebijing(XBJ)can alleviate the inflammatory response,improve organ function,and shorten the intensive care unit(ICU)stay in patients with pyogenic liver abscess(PLA)complicated with sepsis,but the molecula... BACKGROUND:Xuebijing(XBJ)can alleviate the inflammatory response,improve organ function,and shorten the intensive care unit(ICU)stay in patients with pyogenic liver abscess(PLA)complicated with sepsis,but the molecular mechanisms have not been elucidated.This study aimed to explore the molecular mechanism of XBJ in treating PLA complicated with sepsis using a network pharmacology approach.METHODS:The active ingredients and targets of XBJ were retrieved from the ETCM database.Potential targets related to PLA and sepsis were retrieved from the GeneCards,PharmGKB,DisGeNet,Online Mendelian Inheritance in Man(OMIM),Therapeutic Targets Database(TTD),and DrugBank databases.The targets of PLA complicated with sepsis were mapped to the targets of XBJ to identify potential treatment targets.Protein-protein interaction networks were analyzed using the STRING database.Potential treatment targets were imported into the Metascape platform for Gene Ontology(GO)functional enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses.Molecular docking was performed to validate the interactions between active ingredients and core targets.RESULTS:XBJ was found to have 54 potential treatment targets for PLA complicated with sepsis.Interleukin-1β(IL-1β),interleukin-6(IL-6),and tumor necrosis factor(TNF)were identifi ed as core targets.KEGG enrichment analysis revealed important pathways,including the interleukin-17(IL-17)signaling pathway,the TNF signaling pathway,the nuclear factor-kappa B(NF-κB)signaling pathway,and the Toll-like receptor(TLR)signaling pathway.Molecular docking experiments indicated stable binding between XBJ active ingredients and core targets.CONCLUSION:XBJ may exert therapeutic eff ects on PLA complicated with sepsis by modulating signaling pathways,such as the IL-17,TNF,NF-κB,and TLR pathways,and targeting IL-1β,IL-6,and TNF. 展开更多
关键词 Xuebijing injection Pyogenic liver abscess SEPSIS
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C-CORE:Clustering by Code Representation to Prioritize Test Cases in Compiler Testing
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作者 wei zhou Xincong Jiang Chuan Qin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期2069-2093,共25页
Edge devices,due to their limited computational and storage resources,often require the use of compilers for program optimization.Therefore,ensuring the security and reliability of these compilers is of paramount impo... Edge devices,due to their limited computational and storage resources,often require the use of compilers for program optimization.Therefore,ensuring the security and reliability of these compilers is of paramount importance in the emerging field of edge AI.One widely used testing method for this purpose is fuzz testing,which detects bugs by inputting random test cases into the target program.However,this process consumes significant time and resources.To improve the efficiency of compiler fuzz testing,it is common practice to utilize test case prioritization techniques.Some researchers use machine learning to predict the code coverage of test cases,aiming to maximize the test capability for the target compiler by increasing the overall predicted coverage of the test cases.Nevertheless,these methods can only forecast the code coverage of the compiler at a specific optimization level,potentially missing many optimization-related bugs.In this paper,we introduce C-CORE(short for Clustering by Code Representation),the first framework to prioritize test cases according to their code representations,which are derived directly from the source codes.This approach avoids being limited to specific compiler states and extends to a broader range of compiler bugs.Specifically,we first train a scaled pre-trained programming language model to capture as many common features as possible from the test cases generated by a fuzzer.Using this pre-trained model,we then train two downstream models:one for predicting the likelihood of triggering a bug and another for identifying code representations associated with bugs.Subsequently,we cluster the test cases according to their code representations and select the highest-scoring test case from each cluster as the high-quality test case.This reduction in redundant testing cases leads to time savings.Comprehensive evaluation results reveal that code representations are better at distinguishing test capabilities,and C-CORE significantly enhances testing efficiency.Across four datasets,C-CORE increases the average of the percentage of faults detected(APFD)value by 0.16 to 0.31 and reduces test time by over 50% in 46% of cases.When compared to the best results from approaches using predicted code coverage,C-CORE improves the APFD value by 1.1% to 12.3% and achieves an overall time-saving of 159.1%. 展开更多
关键词 Compiler testing test case prioritization code representation
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Euthanasia controversy in China:do we have the right to die?
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作者 wei zhou Chen-Chen Hu +6 位作者 An-Qi Li Qing Wang Yu-Qiang Sun Jia-Yi Si Si-Yi Jin Xin-Yu Wang Jian-Hua Mao 《History & Philosophy of Medicine》 2024年第1期10-13,共4页
This research examines the contentious issue of euthanasia and physician-assisted suicide in the context of China's unique conditions.Historically,the debate over euthanasia has been influenced by moral philosophy... This research examines the contentious issue of euthanasia and physician-assisted suicide in the context of China's unique conditions.Historically,the debate over euthanasia has been influenced by moral philosophy and ethics,and euthanasia is illegal in China at present.The research explores the difficulty in making euthanasia legalized across five key dimensions:financial,medical,social,legal,and psychological factors.We conclude that while there is a desire among some terminally ill patients for euthanasia,the current situation in China makes it unsuitable for legalization.The profound question of one's right to die remains a significant moral and judicial challenge,indicating the need for continued dialogue and nuanced understanding of this complex issue. 展开更多
关键词 EUTHANASIA physician-assisted suicide China LEGISLATION
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Experimental and numerical investigation of Weibullian behavior of grain crushing strength 被引量:3
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作者 Quanshui Huang wei zhou +2 位作者 Gang Ma Tang-Tat Ng Kun Xu 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第2期401-411,共11页
The Weibullian behavior of single grain crushing strength was investigated experimentally and numerically with the aim of enhancing the understanding of rock grain breakage.The morphologies of pebble grains were obtai... The Weibullian behavior of single grain crushing strength was investigated experimentally and numerically with the aim of enhancing the understanding of rock grain breakage.The morphologies of pebble grains were obtained using white light 3D laser scanning and image processing.A grain shape library was constructed for grain shape analysis with different shape descriptors.The use of the shape library and grain stability analysis is discussed for a suggested procedure to rotate a grain to its most stable configuration.Single grain crushing tests were performed for 30 pebbles to obtain force-displacement curves and fracture patterns.Each grain was compressed diametrically between flat platens.As expected,the values of the stress at bulk fracture follow a Weibull distribution.A procedure for generating crushable agglomerates with realistic particle shapes was demonstrated,which was accomplished in the discrete element modeling(DEM)of the single grain crushing test.The work presented here is novel in that both the heterogeneous micro-structures and randomly distributed flaws are considered.The DEM results demonstrate that the proposed modeling approach and calibrated parameters are reliable and can reflect the crushing behavior of rock pebbles.Finally,three parametric studies were presented evaluating the effects of micro-crack density,micro-crack disorder,and grain morphology on the Weibullian behavior of the crushing strength,none of which has previously been thoroughly considered.These three studies provide a deeper insight into the origin of the Weibullian behavior of single grain crushing strength. 展开更多
关键词 Rock grain Grain crushing test Discrete element modeling 3D scanning technique Grain stability Weibullian behavior
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O_(3)对PET微塑料吸附有机污染物的影响机制
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作者 葛建华 辛侠彬 +2 位作者 卫洲 刘丹 张世文 《安徽理工大学学报(自然科学版)》 CAS 2023年第6期53-62,共10页
微塑料对环境污染物具有较高的吸附性能,然而对于微塑料与有机污染物的相互作用方式仍较为缺乏。为了探究O_(3)老化聚对苯二甲酸乙二醇酯微塑料(PET-MPs)与甲基橙的相互影响,通过将微塑料暴露于臭氧中模拟了微塑料在自然环境中的老化过... 微塑料对环境污染物具有较高的吸附性能,然而对于微塑料与有机污染物的相互作用方式仍较为缺乏。为了探究O_(3)老化聚对苯二甲酸乙二醇酯微塑料(PET-MPs)与甲基橙的相互影响,通过将微塑料暴露于臭氧中模拟了微塑料在自然环境中的老化过程,进而改变其物理化学性质,影响其对有机污染物的作用。结果表明,随着老化时间的增加微塑料表面更为粗糙,且存在不规则的孔隙,伴随着结晶度降低、亲水性增强、吸附量减少,微塑料对MO的吸附在24h内基本达到平衡,能够用一级动力学模型较好地拟合(R^(2)>0.98)。吸附等温线更符合Freundlich模型(R^(2)>0.94),属于多层吸附。与水分子之间的氢键作用力增强是导致PET对MO的吸附能力下降的主要原因,不过随着温度的升高,吸附能力也逐渐增强。这一研究结果对于进一步探索微塑料的环境影响提供了理论依据。 展开更多
关键词 微塑料 甲基橙 老化 吸附动力学 吸附等温线
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公众参与行为、社会阶层属性与基本公共服务均等化感知——一个有调节的中介模型
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作者 陈世香 周维 吕志杰 《公共行政评论》 北大核心 2023年第6期167-186,200,共21页
基本公共服务均等化感知是公众对基本公共服务均等化政策执行效果的直观感知,是其在客观获得基础上的主观感受,也是国家治理的良政基准和善治标尺。从公众主观感知视角切入,基于湖北省的一手问卷调查数据,论文采用Bootstrap方法分析公... 基本公共服务均等化感知是公众对基本公共服务均等化政策执行效果的直观感知,是其在客观获得基础上的主观感受,也是国家治理的良政基准和善治标尺。从公众主观感知视角切入,基于湖北省的一手问卷调查数据,论文采用Bootstrap方法分析公众参与行为和社会阶层属性对基本公共服务均等化感知的影响,重点考察行政负担的中介效应和政府形象的调节作用。研究发现,公众参与行为对基本公共服务均等化感知具有显著的正向影响,社会阶层属性对均等化感知具有显著的负向影响;行政负担在公众参与行为和均等化感知之间存在中介效应;政府形象在公众参与行为和均等化感知之间、社会阶层属性和均等化感知之间均发挥着调节作用。研究结果表明,在增强公众参与行为和关注不同社会阶层属性公众的服务需求的同时,也应降低行政负担和改善政府形象,以此提升基本公共服务均等化感知水平。 展开更多
关键词 基本公共服务均等化 公众参与行为 社会阶层属性 行政负担 政府形象
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引入耕地生态价值的咸阳市基本农田划定 被引量:1
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作者 李丁一 魏舟 +3 位作者 童亚文 李莹莹 周传龙 张青峰 《农业工程学报》 EI CAS CSCD 北大核心 2023年第16期256-265,共10页
为了探索科学客观的基本农田划定方法,实现将集中连片和优质稳定的耕地划为基本农田的目标,有效保护耕地和保障国家农业生产安全。该研究以陕西省咸阳市为例,引入耕地生态价值和政策条件多维度评价耕地质量,结合耕地质量空间集聚类型划... 为了探索科学客观的基本农田划定方法,实现将集中连片和优质稳定的耕地划为基本农田的目标,有效保护耕地和保障国家农业生产安全。该研究以陕西省咸阳市为例,引入耕地生态价值和政策条件多维度评价耕地质量,结合耕地质量空间集聚类型划定耕地保护分区;采用缓冲区分析法识别耕地连片性,耦合耕地保护分区和耕地连片等级,尝试探索“连片优先、质量优良、数量约束”的基本农田划定流程。结果表明:1)咸阳市耕地质量划分为高、较高、一般、较低、低5个等级,全市超过一半面积的耕地质量等级为低和较低等级(35.81%和29.67%),一般和较高等级的耕地面积占比也均超过了10%;不同耕地质量等级在空间分布上的差异受地形和区域经济发展影响较大,耕地质量等级总体上呈现出“南高北低”的空间分布格局;咸阳市耕地质量在空间上呈现出明显的集聚特征,以高-高值集聚型和低-低值集聚型耕地为主;2)将全市耕地划为优先保护区、适宜保护区、重点整治区和全面治理区4个保护分区并提出一些保护建议。全面治理区内耕地面积最多,占全市耕地总面积的35.50%,适宜保护区内耕地面积最少,仅占11.81%;3)咸阳市共得到49713个耕地连片地块,面积289033.61 hm^(2),占全市耕地总面积的95.10%。将连片耕地划为6个等级,五级连片耕地面积最多,达到92432.08 hm^(2),一级连片耕地面积最少,为20927.65 hm^(2);4)咸阳市最终划定基本农田面积266420.85 hm^(2),占全市耕地总面积的87.66%,乾县、泾阳县、彬州市和永寿县是重点划定区域,累计划定面积占全市基本农田划定总面积的51.64%。研究方法可为优化耕地布局提供新思路,研究结果在一定程度上可为咸阳市下一阶段的基本农田调整与划定提供借鉴。 展开更多
关键词 耕地 生态价值 质量评价 基本农田划定 保护分区 耕地连片性
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电子封装用Al-Si功能梯度材料的显微组织和性能
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作者 周玮 王日初 +1 位作者 彭超群 蔡志勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CSCD 2023年第12期3583-3596,共14页
通过喷雾沉积法制备用于电子封装的双层和三层Al-Si功能梯度材料。结果表明,梯度材料具有致密的显微组织和良好的层间结合。三层梯度材料的抗弯强度高于双层梯度材料,以高Si含量层为承载面的H-L方向的抗弯强度高于以低Si含量层为承载面... 通过喷雾沉积法制备用于电子封装的双层和三层Al-Si功能梯度材料。结果表明,梯度材料具有致密的显微组织和良好的层间结合。三层梯度材料的抗弯强度高于双层梯度材料,以高Si含量层为承载面的H-L方向的抗弯强度高于以低Si含量层为承载面的L-H方向。所有梯度材料的导热系数均超过140W/(m·K),且其热膨胀系数没有明显的差异。经热冲击处理后,双层梯度材料出现的裂纹比三层梯度材料更多更大,这是由于界面上的高热应力和大尺寸Si颗粒因应力集中而趋于破裂。 展开更多
关键词 电子封装 功能梯度材料 AL-SI合金 有限元分析 抗热震性能
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亚稳β型Ti-6Cr-5Mo-5V-4Al合金的时效析出序列及ω和次生α相对拉伸性能的影响
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作者 周薇 汪畅 +2 位作者 刘继雄 李斯韫 刘会群 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第6期1742-1754,共13页
研究亚稳β型钛合金Ti-6Cr-5Mo-5V-4Al固溶和时效过程中的析出序列及显微组织和拉伸性能之间的关系。在400~450℃时效时,合金析出等温ω相(ω_(iso)),引起高硬化行为和脆性断裂。在450~500℃时效时,随时效时间增加,ω_(iso)相逐渐演化... 研究亚稳β型钛合金Ti-6Cr-5Mo-5V-4Al固溶和时效过程中的析出序列及显微组织和拉伸性能之间的关系。在400~450℃时效时,合金析出等温ω相(ω_(iso)),引起高硬化行为和脆性断裂。在450~500℃时效时,随时效时间增加,ω_(iso)相逐渐演化为次生α相(α_(s))。在更高温度(580~600℃)时效时,ω_(iso)相析出受到抑制,α_(s)相直接从β相析出。由于ω_(iso)相析出,合金在450℃时效12 h时的屈服强度为1368 MPa,伸长率为5.5%。随α_(s)相析出和粗化,合金在600℃时效12 h时的屈服强度为1108 MPa,伸长率提高到15.4%。 展开更多
关键词 亚稳态β-Ti合金 时效序列 Ω相 α_(s)相 强度 塑性
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光催化苯制苯酚的研究进展
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作者 Mengistu Tulu Gonfa 申升 +5 位作者 陈浪 胡彪 周威 白张君 区泽堂 尹双凤 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第6期16-41,共26页
苯酚作为一种重要的有机化学品,广泛用于制造树脂、合成橡胶、染料和药品等行业.然而,传统的苯酚生产方法——联苯法存在着许多问题,如反应条件苛刻和产物纯度低等,这些问题严重制约了苯酚的工业化生产应用.因此,开发一种高效、绿色的... 苯酚作为一种重要的有机化学品,广泛用于制造树脂、合成橡胶、染料和药品等行业.然而,传统的苯酚生产方法——联苯法存在着许多问题,如反应条件苛刻和产物纯度低等,这些问题严重制约了苯酚的工业化生产应用.因此,开发一种高效、绿色的苯酚制备方法十分必要.目前,苯一步法制苯酚反应备受关注,然而,实现该反应难度很大.首先,苯分子的C(sp2)-H键活化在化学反应中比较稳定,难以高效活化.其次,相比惰性反应物苯,产物苯酚分子本身更易氧化,使反应的选择性调控成为挑战.光催化选择性氧化苯制苯酚具有反应条件温和、选择性高和产物纯度高等优点,是一种很有工业应用前景的苯酚制备方法.本文系统总结了近年来多相光催化氧化苯制苯酚的研究进展,包括从光催化剂设计原则、改性策略、反应机理分析、影响反应动力学的因素、反应器设计和光催化剂失活机制等方面.首先,单原子、层状双氢氧化物和金属簇构成的光催化剂具有高效催化作用和良好的反应选择性.其次,在光催化反应过程中,光催化剂的设计和合成是非常关键的,可以通过调节光催化剂的组成和结构来提高反应效率和选择性.此外,基于原位表征和密度泛函理论计算的机理研究也为光催化反应的优化提供了重要的理论基础.此外,介绍了光催化反应器的设计原理和操作要点,以及光催化剂失活的原因和解决方案.在未来的研究中,可以考虑更多的应用新材料和新技术来设计和制备高效催化剂.还可以利用先进的表征和理论计算方法更深入地研究光催化反应的机理,并探索更多的反应条件和催化剂组合,以提高光催化反应的效率和选择性.在实际应用中,光催化反应器的设计和操作也需要进一步完善,以确保光催化反应的稳定性和可控性.随着对光催化反应机理和催化剂设计的深入理解,相信未来光催化苯制苯酚技术会有更多的突破和进展.综上,本文为光催化选择性氧化苯成为苯酚的研究提供了参考,也为光催化反应的设计、优化和应用提供了一定的思路. 展开更多
关键词 苯酚 直接氧化 光催化剂 光反应器
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Detecting Vulnerability on IoT Device Firmware: A Survey 被引量:2
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作者 Xiaotao Feng Xiaogang Zhu +3 位作者 Qing-Long Han wei zhou Sheng Wen Yang Xiang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第1期25-41,共17页
Internet of things (IoT) devices make up 30%of all network-connected endpoints,introducing vulnerabilities and novel attacks that make many companies as primary targets for cybercriminals.To address this increasing th... Internet of things (IoT) devices make up 30%of all network-connected endpoints,introducing vulnerabilities and novel attacks that make many companies as primary targets for cybercriminals.To address this increasing threat surface,every organization deploying IoT devices needs to consider security risks to ensure those devices are secure and trusted.Among all the solutions for security risks,firmware security analysis is essential to fix software bugs,patch vulnerabilities,or add new security features to protect users of those vulnerable devices.However,firmware security analysis has never been an easy job due to the diversity of the execution environment and the close source of firmware.These two distinct features complicate the operations to unpack firmware samples for detailed analysis.They also make it difficult to create visual environments to emulate the running of device firmware.Although researchers have developed many novel methods to overcome various challenges in the past decade,critical barriers impede firmware security analysis in practice.Therefore,this survey is motivated to systematically review and analyze the research challenges and their solutions,considering both breadth and depth.Specifically,based on the analysis perspectives,various methods that perform security analysis on IoT devices are introduced and classified into four categories.The challenges in each category are discussed in detail,and potential solutions are proposed subsequently.We then discuss the flaws of these solutions and provide future directions for this research field.This survey can be utilized by a broad range of readers,including software developers,cyber security researchers,and software security engineers,to better understand firmware security analysis. 展开更多
关键词 Firmware emulation internet of things(IoT)firmware network fuzzing security static analysis
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含碳纳米管包覆Co9S8微球的高性能铵离子电池正极材料
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作者 黄玉柱 幸琳 +6 位作者 裴双 周伟 胡宇杰 邓维娜 陈亮 朱海 陈晗 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第11期3452-3464,共13页
构建Co9S8/碳纳米管(Co9S8/2CNTs)涂层微球,并成功将其应用于水性铵离子电池。在Co9S8微球中引入碳纳米管可增加电子传导性,缩短NH4+离子的扩散距离,并提高对循环过程中体积变化的缓冲能力。因此,Co9S8/2CNTs微球在0.1A/g条件下具有112m... 构建Co9S8/碳纳米管(Co9S8/2CNTs)涂层微球,并成功将其应用于水性铵离子电池。在Co9S8微球中引入碳纳米管可增加电子传导性,缩短NH4+离子的扩散距离,并提高对循环过程中体积变化的缓冲能力。因此,Co9S8/2CNTs微球在0.1A/g条件下具有112mA·h/g的可逆容量。此外,研究了Co9S8/2CNTs中伴随着可逆相变产物CoSO_(4)·6H_(2)O的形成和分子间氢键的形成/断裂的铵离子储能机理。 展开更多
关键词 硫化钴 碳纳米管 铵离子电池 复合微球 氢键
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In situ formation of self-antistacking FeCoO_(x) on N-doped graphene:A 3D-on-2D nanoarchitecture for long-life Zn-air batteries 被引量:1
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作者 Zehao Zheng Cuie Wang +5 位作者 Peng Mao Yijun Zhu Ran Ran wei zhou Kaiming Liao Zongping Shao 《Carbon Energy》 SCIE CSCD 2023年第3期87-97,共11页
Before the practical application of rechargeable Zn-air batteries(ZABs),a critical issue regarding the inherent slow reaction kinetics of the oxygen reduction(ORR)and oxygen evolution(OER)must be addressed.Here,we fab... Before the practical application of rechargeable Zn-air batteries(ZABs),a critical issue regarding the inherent slow reaction kinetics of the oxygen reduction(ORR)and oxygen evolution(OER)must be addressed.Here,we fabricate a cost-effective bifunctional oxygen electrocatalyst with a self-antistacking structure,where three-dimensional(3D)Fe-Co bimetallic oxide particles(FeCoO_(x))are directly grown on 2D N-doped graphene(NG).The in situ grown FeCoO_(x)particles can alleviate the NG interlaminar restacking,ensuring abundant channels for diffusion of O_(2)/OH−species,while the NG allows rapid electron flow.Benefiting from this self-antistacking 3D-on-2D structure and synergetic electrocatalysis,FeCoO_(x)@NG demonstrated excellent activity for both ORR and OER(ΔE=0.78 V),which is superior to that of the binary mixtures of Pt/C and RuO_(2)(ΔE=0.83 V).A homemade ZAB with 20%-FeCoO_(x)@NG delivers a specific capacity of 758.9 mAh g^(−1),a peak power density of 215 mW cm^(−2),and long-term cyclability for over 400 h.These research results suggest that designing a bimetallic oxide/N-doped carbon 3D-on-2D nanoarchitecture using an in situ growth strategy is an attractive and feasible solution to overcome electrocatalytic problems in ZABs. 展开更多
关键词 antistacking nanostructure in situ growth oxygen electrocatalysts Zn-air batteries
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参附注射液联合瑞舒伐他汀对合并冠心病胃癌手术切除患者心肌损伤及不良事件发生率的影响
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作者 周威 张占丰 《世界华人消化杂志》 CAS 2023年第16期688-694,共7页
背景冠心病胃癌手术切除患者由于冠心病及手术双重影响,术后风险性较高,且应激反应较大,会影响手术恢复及术中安全性.参附注射液作为一种中药制剂,在改善心脏功能、减轻心脏手术应激、保护心肌等方面均有显著作用,期望通过围术期用药减... 背景冠心病胃癌手术切除患者由于冠心病及手术双重影响,术后风险性较高,且应激反应较大,会影响手术恢复及术中安全性.参附注射液作为一种中药制剂,在改善心脏功能、减轻心脏手术应激、保护心肌等方面均有显著作用,期望通过围术期用药减轻术中应激,提高手术安全性,促进术后恢复.目的探讨参附注射液联合瑞舒伐他汀在合并冠心病胃癌手术切除患者中的应用效果.方法选取2018-07/2021-07我院冠心病胃癌手术切除患者86例,以随机数字表法分为研究组、对照组,各43例.两组均采取全麻,于此基础上对照组瑞舒伐他汀,研究组予以参附注射液联合瑞舒伐他汀.对比两组术后恢复情况以及术前、术后12 h、术后24 h炎症指标[超敏-C反应蛋白(high sensitivity C-reactive protein,hs-CRP)、肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)、白细胞介素-6(interleukin-6,IL-6)]、应激反应指标[皮质醇(corticosteroids,Cor)、促肾上腺皮质激素(adrenocorticotrophic hormone,ACTH)、肾上腺素(epinephrine,E)]、心肌损伤指标[肌酸激酶同工酶(creatine kinase isoenzyme,CK-MB)、心肌肌钙蛋白Ⅰ(cardiactroponin I,cTnⅠ)]、术前、术后3 d心功能指标[左心室射血分数(left ventricular ejection fraction,LVEF)、心脏指数(cardiac index,CI)、心排量(cardiac output,CO)]水平,并统计两组术后3 d心脏不良事件.结果研究组术后住院时间、首次排便时间、首次肛门排气时间、肠鸣音恢复时间均较对照组短(P<0.05);与术前相比,两组术后12 h、24 h血清hs-CRP、TNF-α、IL-6、Cor、ACTH、E、CK-MB、cTnⅠ水平均较本组术前增高,但研究组低于对照组(P<0.05);两组术后3 d的LVEF、CI、CO水平均较本组术前提高,且研究组高于对照组(P<0.05);研究组术后3 d心脏不良事件发生率11.63%与对照组23.26%相比,差异无统计学意义.结论参附注射液联合瑞舒伐他汀应用于冠心病胃癌手术切除患者可减轻炎症应激反应,减轻心肌损伤,促进患者恢复. 展开更多
关键词 参附注射液 瑞舒伐他汀 冠心病 胃癌 心肌损伤 心脏不良事件
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重铬酸钾法对城镇污水处理厂污水中COD的测定
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作者 魏洲 徐昊 +2 位作者 赵玛丽 吴浩然 朴哲 《山东化工》 CAS 2023年第15期156-158,共3页
对于城镇污水处理厂污水COD的测定,我国规定使用重铬酸盐法,并于2017年5月1日开始实施《水质化学需氧量的测定重铬酸盐法》(HJ 828—2017)。本文简要分析了新旧国标法中的修订情况,结合本课题组使用重铬酸钾法测定废水处理中COD含量的... 对于城镇污水处理厂污水COD的测定,我国规定使用重铬酸盐法,并于2017年5月1日开始实施《水质化学需氧量的测定重铬酸盐法》(HJ 828—2017)。本文简要分析了新旧国标法中的修订情况,结合本课题组使用重铬酸钾法测定废水处理中COD含量的实验操作情况,重点阐述重铬酸钾法基本原理及具体测定方法,并总结出该方法在测量过程中的重要影响因素以及解决措施。 展开更多
关键词 城镇污水 重铬酸钾法 化学需氧量 新旧国标对比
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Inosine:A broad-spectrum anti-inflammatory against SARS-CoV-2 infection-induced acute lung injury via suppressing TBK1 phosphorylation
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作者 Ningning Wang Entao Li +9 位作者 Huifang Deng Lanxin Yue Lei zhou Rina Su Baokun He Chengcai Lai Gaofu Li Yuwei Gao wei zhou Yue Gao 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第1期11-23,共13页
Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-induced cytokine storms constitute the primary cause of coronavirus disease 19(COVID-19)progression,severity,criticality,and death.Glucocorticoid and anti-cy... Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)-induced cytokine storms constitute the primary cause of coronavirus disease 19(COVID-19)progression,severity,criticality,and death.Glucocorticoid and anti-cytokine therapies are frequently administered to treat COVID-19,but have limited clinical efficacy in severe and critical cases.Nevertheless,the weaknesses of these treatment modalities have prompted the development of anti-inflammatory therapy against this infection.We found that the broad-spectrum anti-inflammatory agent inosine downregulated proinflammatory interleukin(IL)-6,upregulated anti-inflammatory IL-10,and ameliorated acute inflammatory lung injury caused by multiple infectious agents.Inosine significantly improved survival in mice infected with SARS-CoV-2.It indirectly impeded TANK-binding kinase 1(TBK1)phosphorylation by binding stimulator of interferon genes(STING)and glycogen synthase kinase-3β(GSK3β),inhibited the activation and nuclear translocation of the downstream transcription factors interferon regulatory factor(IRF3)and nuclear factor kappa B(NF-κB),and downregulated IL-6 in the sera and lung tissues of mice infected with lipopolysaccharide(LPS),H1N1,or SARS-CoV-2.Thus,inosine administration is feasible for clinical anti-inflammatory therapy against severe and critical COVID-19.Moreover,targeting TBK1 is a promising strategy for inhibiting cytokine storms and mitigating acute inflammatory lung injury induced by SARS-CoV-2 and other infectious agents. 展开更多
关键词 CYTOKINE stormInterleukin 6 (IL-6)InosineSARS-CoV-2TANK-binding kinase 1 (TBK1)
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Selectivity control of photocatalytic CO_(2) reduction over ZnS-based nanocrystals:A comparison study on the role of ionic cocatalysts
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作者 Hong Pang Fumihiko Ichihara +4 位作者 Xianguang Meng Lijuan Li Yuqi Xiao wei zhou Jinhua Ye 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第11期391-398,I0009,共9页
Taking copper doped ZnS(ZnS:Cu)nanocrystals as the main body of photocatalyst,the influence of different base transition metal ions(M^(2+)=Ni^(2+),Co^(2+),Fe^(2+)and Cd^(2+))on photocatalytic CO_(2)reduction in inorga... Taking copper doped ZnS(ZnS:Cu)nanocrystals as the main body of photocatalyst,the influence of different base transition metal ions(M^(2+)=Ni^(2+),Co^(2+),Fe^(2+)and Cd^(2+))on photocatalytic CO_(2)reduction in inorganic reaction system is investigated.Confined single-atom Ni^(2+),Co^(2+),and Cd^(2+)sites were created via cation-exchange process and enhanced CO_(2)reduction,while Fe^(2+)suppressed the photocatalytic activity for both water and CO_(2)reduction.The modified ZnS:Cu photocatalysts(M/ZnS:Cu)demonstrated tunable product selectivity,with Ni^(2+)and Co^(2+)showing high selectivity for syngas production and Cd^(2+)displaying remarkable formate selectivity.DFT calculations indicated favorable H adsorption free energy on Ni^(2+)and Co^(2+)sites,promoting the hydrogen evolution reaction.The selectivity of CO_(2)reduction products was found to be sensitive to the initial intermediate adsorption states.*COOH formed on Ni^(2+)and Co^(2+)while*OCHO formed on Cd^(2+),favoring the production of CO and HCOOH as the main products,respectively.This work provides valuable insights for developing efficient solar-to-fuel platforms with controlled CO_(2)reduction selectivity. 展开更多
关键词 CO_(2) reduction Photocatalysis Zns Ionic cocatalyst FORMATE Syngas DFT calculations
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Effect of gravel on rock failure in glutenite reservoirs under different confining pressures
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作者 Jian-Tong Liu Jian-Bo Wang +5 位作者 Hong-Kui Ge wei zhou Bei-Bei Chen Xiao-Di Li Xian-Jie Xue Sen-Lin Luo 《Petroleum Science》 SCIE EI CSCD 2023年第5期3022-3036,共15页
Due to the existence of gravel,glutenite is heterogeneous and different from fine-grained rocks such as sandstone and shale in structure.To fully understand the effect of gravel on failure mode in glutenite,we perform... Due to the existence of gravel,glutenite is heterogeneous and different from fine-grained rocks such as sandstone and shale in structure.To fully understand the effect of gravel on failure mode in glutenite,we performed triaxial compression tests on different glutenites.The results indicate that failure modes of glutenite are complex due to the existence of gravel.Under different confining pressures,three failure modes were observed.The first failure mode,a tensile failure under uniaxial compression,produces multiple tortuous longitudinal cracks.In this failure mode,the interaction between gravels provides the lateral tensile stress for rock splitting.The second failure mode occurs under low and medium confining pressure and produces a crack band composed of micro-cracks around gravels.This failure mode conforms to the Mohr-Coulomb criterion and is generated by shear failure.In this failure mode,shear dilatancy and shear compaction may occur under different confining pressures to produce different crack band types.In the second failure mode,gravel-induced stress concentration produces masses of initial micro-cracks for shear cracking,and gravels deflect the fracture surfaces.As a result,the fracture is characterized by crack bands that are far broader than in fine-grained rocks.The third failure mode requires high confining pressure and produces disconnected cracks around gravels without apparent crack bands.In this failure mode,the gravel rarely breaks,indicating that the formation of these fractures is related to the deformation of the matrix.The third failure mode requires lower confining pressure in glutenite with weak cement and matrix support.Generally,unlike fine-grained rocks,the failure mode of glutenite is not only controlled by confining pressure but also by the gravel.The failure of glutenite is characterized by producing cracks around gravels.These cracks are produced by different mechanisms and distributed in different manners under different confining pressures to form different fracture patterns.Therefore,understanding the rock microstructure and formation stress state is essential in guiding glutenite reservoir development. 展开更多
关键词 GLUTENITE HETEROGENEITY Failure mode Triaxial compression test Shear dilatancy Shear compaction
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