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Progress in the Study of Microwave Pyrolysis Technology and Its Influencing Factors
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作者 Hui Fang Lin Hai +2 位作者 Ruisheng Xie jing yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第10期30-61,共32页
In recent years, the effective conversion of organic wastes into valuable products has been a focus and difficulty in sustainable energy and environmental management. Organic wastes come from a wide range of sources, ... In recent years, the effective conversion of organic wastes into valuable products has been a focus and difficulty in sustainable energy and environmental management. Organic wastes come from a wide range of sources, and industrial and agricultural sources are the main sources of organic waste in China, which can be controlled by microwave pyrolysis technology. In microwave pyrolysis treatment, catalysts have been the key material, microwave absorber, and catalyst of the research hotspot in recent years. This paper summarises the typical influencing parameters of microwave pyrolysis (including microwave power, pyrolysis temperature and microwave absorber), and also summarises the various catalysts applied in microwave pyrolysis, and looks forward to the potential application prospect of pyrolysis products, and the future development direction. 展开更多
关键词 MICROWAVE Microwave Pyrolysis Microwave-Catalysed Pyrolysis CATALYST Microwave Absorber Microwave Power Renewable Energy
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Adsorption of Phenanthrene in Soil to Biochar Modified by β-Cyclodextrin
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作者 Wanke Chen Qing Guo +3 位作者 Xiaoyan Wang Xiao Wang jing yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第9期44-54,共11页
In this study, the adsorption effect of β-cyclodextrin modified biochar (BC) on phenanthrene (PHE) in contaminated soil was investigated, aiming to provide an efficient and environmentally friendly remediation strate... In this study, the adsorption effect of β-cyclodextrin modified biochar (BC) on phenanthrene (PHE) in contaminated soil was investigated, aiming to provide an efficient and environmentally friendly remediation strategy for Polycyclic Aromatic Hydrocarbons (PAHs) contaminated soil. Through kinetic and isotherm analysis, β-CDBC-CA showed excellent phenanthrene adsorption performance, and the adsorption effect increased with the increase of time and was affected by temperature. The results show that β-CDBC-CA can not only effectively adsorb phenanthrene in soil, but also serve as a surfactant to help desorption phenanthrene adsorbed by soil organic matter and improve the efficiency of microbial degradation. The experimental data showed that the Elovich model could describe the adsorption behavior of β-CDBC-CA on phenanthrene well, while Langmuir and Freundlich models performed better in fitting parameters, revealing the adsorption mechanism of phenanthrene in contaminated soil by β-cyclodextrin-modified biochar. In addition, temperature has a significant effect on the adsorption capacity of β-CDBC-CA, and its application in soil remediation can be optimized by adjusting temperature. This study not only provides new materials and technical means for soil remediation but also provides important data support for an in-depth understanding of the environmental behavior of PAHs. By citing relevant research results, this study further improves the control and understanding of environmental risks of PAHs, which is of great significance for the protection of ecological environment and human health. 展开更多
关键词 PAHS BIOCHAR Β-CYCLODEXTRIN MODIFICATION ADSORPTION Soil Remediation
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Modification of Nano-α-Al2O3 and Its Influence on the Surface Properties of Waterborne Polyurethane Resin Composite Passivation Films
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作者 Jiankang Fu Changshuai Ma +2 位作者 Yameng Zhu jing yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第5期29-48,共20页
Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub&... Silane coupling agent KH560 was used to modify the surface of nano-α-Al<sub>2</sub>O<sub>3</sub> in ethanol-aqueous solution with different proportions. The particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> was determined by nano-particle size analyzer, and the effects of nano-α-Al<sub>2</sub>O<sub>3</sub> content, ethanol-aqueous solution ratio and KH560 dosage on the dispersion and particle size of nano-α-Al<sub>2</sub>O<sub>3</sub> were investigated. The material structure before and after modification was determined by Fourier transform infrared spectroscopy (FTIR). Aqueous polyurethane resin and inorganic components are combined with modified nano-α-Al<sub>2</sub>O<sub>3</sub> dispersion to form chromium-free passivation solution. The solution is coated on the galvanized sheet, the adhesion and surface hardness are tested, the bonding strength of the coating and the surface hardness of the substrate are discussed. The corrosion resistance and surface morphology of the matrix were investigated by electrochemical test, neutral salt spray test and scanning electron microscope test. The chromium-free passivation film formed after the modification of nano-α-Al<sub>2</sub>O<sub>3</sub> increases the surface hardness of galvanized sheet by about 85%. The corrosion resistance of the film is better than that of a single polyurethane film. The results show that the surface hardness and corrosion resistance of polyurethane resin composite passivation film are significantly improved by the introduction of nano-α-Al<sub>2</sub>O<sub>3</sub>. 展开更多
关键词 Micro-Nano α-Al2O3 Waterborne Polyurethane Resin Particle Size Surface Hardness Corrosion Resistance
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Synthesis and Characterization of β-Cyclodextrin Modified Biochar Environmental Remediation Materials
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作者 Qing Guo Xiao Wang +3 位作者 Wanke Chen Xiaoyan Wang jing yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第4期42-52,共11页
In this paper, biochar (BC) was used as raw material, activated by deionizing aqueous solution, NaCl solution, CA solution and HCl solution respectively. Epichlorohydrin (EPI) was used as crosslinking agent, and β-cy... In this paper, biochar (BC) was used as raw material, activated by deionizing aqueous solution, NaCl solution, CA solution and HCl solution respectively. Epichlorohydrin (EPI) was used as crosslinking agent, and β-cyclodextrin (β-CD) was used to modify biochar (BC). The prepared modified biochar materials were labeled with β-CDBC, β-CDBC-Na, β-CDBC-CA and β-CDBC-H, respectively. The infrared spectrum, X-ray diffractometer, scanning electron microscope and specific surface area of the four modified materials were tested. The results showed that the C-O stretching vibration peak at 1020 cm<sup>−</sup><sup>1</sup> of the modified materials was slightly offset compared with that of biochar. The characteristic absorption peaks of XRD pattern decrease obviously at 2θ = 26.7˚ and 29.5˚. It can be obviously observed on the electron microscope image that the surface is loaded or formed clathrates, and BET data and graphs also show that the specific surface area of the modified biochar is larger. Therefore, β-cyclodextrin successfully modified biochar and formed clathrates on the surface of biochar or was loaded in the pore structure of biochar, especially β-CDBC-CA achieved better modification effect. Because biochar and β-cyclodextrin raw materials are cheap, easy to prepare and green, and less prone to secondary pollution, it has a good advantage in environmental governance. 展开更多
关键词 BIOCHAR Β-CYCLODEXTRIN MODIFICATION CLATHRATE Green Environmental Protection
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Volatile Organic Compounds (VOCs) in China: Progress and Prospects of Research on Treatment Technologies and Policy Provisions
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作者 Lixia Wu Yu Zhu +2 位作者 jing yuan Xiaozhong Guo Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第9期1-43,共43页
Volatile organic compounds (VOCs) are an atmospheric pollutant with a boiling point of 50˚C - 260˚C at room temperature and pressure. They are precursors of sulfur dioxide and ozone, which can seriously pollute the at... Volatile organic compounds (VOCs) are an atmospheric pollutant with a boiling point of 50˚C - 260˚C at room temperature and pressure. They are precursors of sulfur dioxide and ozone, which can seriously pollute the atmosphere and endanger human health. After the “14th Five-Year Plan”, VOCs, instead of SO2, became one of the five indicators of China’s atmospheric governance. As a result, the government’s efforts to control VOCs have increased significantly. VOCs governance mustn’t be delayed. This paper provides a comprehensive summary and analysis of VOCs governance, covering the classification of VOCs, analysis of VOC governance technology (with a focus on end-of-pipe governance technology), national policy regulations, current governance shortcomings, and a forward-looking perspective on the future direction of VOCs governance, emphasizing healthy and sustainable development. 展开更多
关键词 Volatile Organic Compounds VOCS End-of-Pipe Treatment Technology Policy Regulations
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中国学者论文被引频次与基金项目资助关系探究
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作者 经渊 杨一舟 《科技管理研究》 CSSCI 2024年第15期221-226,共6页
为探究论文被引频次与基金资助之间的关系,选取中国学者2017年发表在中国科学引文数据库(CSCD)和科学引文索引扩展版(SCI-E)数据库收录期刊的论文,分析了不同基金项目资助条件下论文被引频次的幂律分布规律。基金论文的被引频次整体上... 为探究论文被引频次与基金资助之间的关系,选取中国学者2017年发表在中国科学引文数据库(CSCD)和科学引文索引扩展版(SCI-E)数据库收录期刊的论文,分析了不同基金项目资助条件下论文被引频次的幂律分布规律。基金论文的被引频次整体上高于非基金论文,但具体提升程度与研究方向有关。对学者而言没有必要在一篇论文后挂多个基金项目,对期刊而言不需要过度追求基金论文比,这两个指标与被引频次之间均未呈现出正相关性。应客观看待基金项目的作用,加强期刊评价研究,全面评价论文、期刊的质量和影响力,规范基金项目标注,合理利用基金论文比指标,坚守科技期刊办刊本心。受模型和数据限制,零被引的长尾论文及人文学科论文的基金项目资助作用规律尚未得到有效揭示。 展开更多
关键词 基金项目 科技期刊 基金论文比 被引频次 CSCD SCI-E 幂律
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Feasibility Analysis of the Sintering Flue Gas Oxidation Method for Denitrification Technology Route
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作者 Weiling Chu Linling Wu +1 位作者 jing yuan Qianfeng Zhang 《Journal of Materials Science and Chemical Engineering》 2024年第6期12-23,共12页
With the vigorous development of China’s iron and steel industry and the introduction of ultra-low emission policies, the emission of pollutants such as SO2 and NOx has received unprecedented attention. At present, t... With the vigorous development of China’s iron and steel industry and the introduction of ultra-low emission policies, the emission of pollutants such as SO2 and NOx has received unprecedented attention. At present, the commonly used denitrification methods include selective catalytic reduction (SCR), active coke, etc. As a newly developed denitrification technology, oxidation denitrification is not widely used, and the technical level is mixed, and there might be problems such as yellow smoke, secondary pollution and ozone escape in the practical application. In this paper, problems existing in the denitrification process of sintering flue gas oxidation are analyzed, and a 320 m2 sintering machine is taken as an example. Comparing the denitrification technology of sintering industry, it could be seen that the denitrification technology route of oxidation method has low pollution, low cost and high comprehensive environmental benefits, and has greatly potential development. 展开更多
关键词 SINTERING Air Pollution Denitration by Oxidation
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基于三维特征构建和扩张残差网络的机械故障音频识别方法
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作者 景源 李孟鼎 《辽宁大学学报(自然科学版)》 CAS 2024年第3期220-231,共12页
已有的基于音频的机械故障识别方法,大多是使用二维神经网络和音频信号的某个单一特征(如功率谱)进行故障检测,然而单一的音频特征在提取过程中可能会存在关键信息丢失的现象,且往往只能提取音频特征的单一维度(如空间上)信息,这极大限... 已有的基于音频的机械故障识别方法,大多是使用二维神经网络和音频信号的某个单一特征(如功率谱)进行故障检测,然而单一的音频特征在提取过程中可能会存在关键信息丢失的现象,且往往只能提取音频特征的单一维度(如空间上)信息,这极大限制了现有设备故障音频算法的有效性.为了探究解决上述问题的方法,本文提出一种包含不同音频特征的三维特征构建方式,利用不同的音频特征弥补特征提取过程中的关键信息;并且构建了三维扩张残差网络模型(DR-3DCNN),采用空洞卷积的方式增大模型对全局的关注,同时获取不同尺度的特征信息;充分利用不同特征之间的相关性,建立特征与原始音频数据的深层次关联;最后,采用公开的故障工业机器调查和检查数据集(MIMII)进行实验.实验结果表明,三维特征和DR-3DCNN相组合的方式,其机械故障识别分类效果有了显著提升,分类准确率好于以往单一音频特征的识别算法. 展开更多
关键词 机械故障识别 三维卷积网络(3DCNN) 三维特征构建 空洞卷积
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中国人群33104例单基因病携带者筛查的多中心研究 被引量:3
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作者 侯伟 付晓琳 +17 位作者 谢潇潇 张春燕 边佳昕 毛翛 文娟 罗春玉 金华 祝茜 戚庆炜 钱叶青 袁静 赵彦艳 尹爱兰 李树铁 蒋宇林 张蔓丽 肖锐 卢彦平 《南方医科大学学报》 CAS CSCD 北大核心 2024年第6期1015-1023,共9页
目的 通过大规模多中心的多种遗传病携带者筛查,调查中国人群单基因病的流行病学特征以及突变谱,为制定适合中国人群的遗传病预防策略提供依据。方法 本研究在中国的12个临床中心共招募33 104例受检者(16 610例女性),基于高通量测序和多... 目的 通过大规模多中心的多种遗传病携带者筛查,调查中国人群单基因病的流行病学特征以及突变谱,为制定适合中国人群的遗传病预防策略提供依据。方法 本研究在中国的12个临床中心共招募33 104例受检者(16 610例女性),基于高通量测序和多种PCR对223个基因的携带者状态进行检测。结果 197个常染色体基因的合并携带者频率为55.58%,26个X连锁基因的合并携带者频率为1.84%。在16 669例家系中,共检出874对(5.24%)高危夫妇。其中常染色体基因高危夫妇584对(3.50%),X连锁基因高危夫妇306对(1.84%),16对夫妇同时为常染色体基因和X连锁基因高危夫妇。最常检出的常染色体高危基因包括GJB2(常染色体隐性耳聋1A,393对),HBA1/HBA2(α-地中海贫血,36对)和PAH(苯丙酮尿症,14对),SMN1(脊髓性肌萎缩症,14对)。最常检出的X连锁高危基因包括G6PD(G6PD缺乏症,236对),DMD(进行性假肥大性肌营养不良,23对)和FMR1(脆性X综合征,17对)。除外G6PD后的高危夫妇率为3.91%(651/16 669),进一步除外GJB2 c.109G>A位点后,高危夫妇率为1.72%(287/16 669)。理论上严重的单基因病出生缺陷的发病率约为4.35‰(72.5/16 669)。对导致高危夫妇最多的22个基因进行筛查可检出95%以上的高危夫妇,对导致高危夫妇最多的54个基因进行筛查可检出99%以上的高危夫妇。结论 本研究揭示了我国人群中223种单基因病的携带者频率,为中国人群的携带者筛查策略制定和panel设计提供依据。在携带者筛查实践中,针对某些特殊基因或变异位点的遗传咨询可能会面临困难。这些特殊基因或变异需要在检测前告知受检夫妇,并在可能的情况下提供不筛查这些基因或变异的选择。 展开更多
关键词 携带者筛查 单基因病 遗传咨询
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我国静电纺丝领域研究现状及其热点:基于CNKI数据库的可视化文献计量分析 被引量:13
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作者 苏芳芳 经渊 +1 位作者 宋立新 唐志荣 《东华大学学报(自然科学版)》 CAS 北大核心 2024年第1期45-54,共10页
基于CNKI数据库,利用CiteSpace可视化计量学方法分析国内静电纺丝领域的发文量、作者和机构合作状况以及研究主题的演化,并与国际上2018-2022年的研究主题进行对比。分析发现:国内作者在静电纺丝领域的发文量呈现逐年增加趋势;作者共现... 基于CNKI数据库,利用CiteSpace可视化计量学方法分析国内静电纺丝领域的发文量、作者和机构合作状况以及研究主题的演化,并与国际上2018-2022年的研究主题进行对比。分析发现:国内作者在静电纺丝领域的发文量呈现逐年增加趋势;作者共现的局部网络密度大,整体网络密度小;参与静电纺丝研究的高校之间合作密切;国内静电纺丝领域的研究主要集中在纤维的制备,及纳米纤维在生物医药、空气过滤、水处理、能源器件、防护、传感等领域的应用等方面,与国际上在静电纺丝领域的研究热点有较高的相似性。 展开更多
关键词 静电纺丝 文献计量 可视化 纳米纤维 CITESPACE
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基于核心素养的高校英语教学的创新发展研究
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作者 李梦洋 井媛 +1 位作者 陈耀庭 杨坤 《湖北开放职业学院学报》 2024年第11期6-8,共3页
英语是现阶段高校教学实践中说道普遍关注的学科之一,分析研究英语的教学目标和方向,并对英语教学的创新发展做分析与讨论,这对于推进英语教学改革,提升英语教学实效有突出的现实意义。目前,核心素养教育理念越来越深入人心,在核心素养... 英语是现阶段高校教学实践中说道普遍关注的学科之一,分析研究英语的教学目标和方向,并对英语教学的创新发展做分析与讨论,这对于推进英语教学改革,提升英语教学实效有突出的现实意义。目前,核心素养教育理念越来越深入人心,在核心素养教育的具体要求下,高校的英语教学需要做积极的调整,包括教学方法的调整、教学模式的调整、教学目标的调整等。总的来讲,对核心素养背景下的高校英语教学发展目标进行明确,并在目标基础上强调英语教学的创新发展策略,这对于指导当前教育有突出现实价值。文章基于核心素养分析高校英语教学的创新发展,旨在为当前教育实践提供参考与帮助。 展开更多
关键词 核心素养 高校 英语教学 创新发展
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无机矿物填料对天然橡胶复合材料硫化特性和力学性能的影响
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作者 赵蒙 韩林峰 +4 位作者 段昊 彭可瑜 张林 井源 林广义 《弹性体》 CAS 2024年第3期37-41,49,共6页
无机矿物填料对橡胶复合材料的性能具有重要影响,主要研究了包括微晶石墨(GM6)、微型硅酸盐(MS-1)、粉煤灰(FA)和砖粉(BP)等无机矿物填料对天然橡胶(NR)复合材料的硫化特性和力学性能的影响。结果表明,当微晶石墨(GM6)被用作填料时,橡... 无机矿物填料对橡胶复合材料的性能具有重要影响,主要研究了包括微晶石墨(GM6)、微型硅酸盐(MS-1)、粉煤灰(FA)和砖粉(BP)等无机矿物填料对天然橡胶(NR)复合材料的硫化特性和力学性能的影响。结果表明,当微晶石墨(GM6)被用作填料时,橡胶复合材料表现出最高的最高转矩与最低转矩的差值(M_(H)-M_(L))值和最快的硫化时间。此外,该复合材料在拉伸强度、撕裂强度、硬度和耐磨性方面均表现出最佳性能,而断裂伸长率没有明显的差异。该研究发现为无机矿物材料在橡胶中的应用和优化提供了参考。 展开更多
关键词 无机矿物材料 天然橡胶 硫化特性 力学性能 抗热氧老化性
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天然次生林中小斑啄木鸟的取食偏好
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作者 荆媛 魏爽 +3 位作者 史文辉 马梓贺 王德宇 戎可 《野生动物学报》 北大核心 2024年第1期84-94,共11页
2022年3—6月,于黑龙江帽儿山森林生态系统国家野外科学观测研究站开展小斑啄木鸟(Dryobates minor)取食偏好的调查。采用样方结合样线与无线电追踪技术追踪小斑啄木鸟,采用基于“利用-可利用型”方法的Bailey’s方法分析小斑啄木鸟取... 2022年3—6月,于黑龙江帽儿山森林生态系统国家野外科学观测研究站开展小斑啄木鸟(Dryobates minor)取食偏好的调查。采用样方结合样线与无线电追踪技术追踪小斑啄木鸟,采用基于“利用-可利用型”方法的Bailey’s方法分析小斑啄木鸟取食树木与取食生境的偏好,采用主成分分析归纳影响选择取食地的主要因子,利用Fisher’s精确检验、非参数检验和相关性检验探究性别在取食行为中及主要因子间的差异。结果显示:小斑啄木鸟偏好在活立木上,用轻啄的方式,在冠层处、侧枝上短时取食;株密度、取食树高度、坡度、优势种、最近人为干扰距离与样方内树的均高是影响小斑啄木鸟选择取食树木与取食生境的主要因子;小斑啄木鸟偏好在株密度适中、取食树的高度约15 m、平坡处、以春榆(Ulmus davidiana var.japonica)或胡桃楸(Juglans mandshurica)为优势种、靠近人为干扰和样方内树均高约13 m的生境内取食;与雌性相比,雄性还偏好在株密度较低、株高在3~5 m的树木上取食。 展开更多
关键词 小斑啄木鸟 取食偏好 取食行为 取食树木 取食生境
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阔叶红松林中黑啄木鸟的取食生境偏好
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作者 于美辰 陈俊达 +3 位作者 司雨蕙 魏爽 荆媛 戎可 《野生动物学报》 北大核心 2024年第2期328-337,共10页
2020年冬季—2022年冬季,采用样线法和样方法对黑龙江省凉水国家级自然保护区中黑啄木鸟(Dryocopus martius)取食生境偏好进行调查研究,结果表明:在取食微生境尺度中,黑啄木鸟取食树树种、取食树状态与对照样方具有显著差异(p<0.05)... 2020年冬季—2022年冬季,采用样线法和样方法对黑龙江省凉水国家级自然保护区中黑啄木鸟(Dryocopus martius)取食生境偏好进行调查研究,结果表明:在取食微生境尺度中,黑啄木鸟取食树树种、取食树状态与对照样方具有显著差异(p<0.05),偏好在冷杉(Abies fabri,47.71%)和半枯立木(73.86%)的树木主干(86.93%)中上部(43.14%)、上部(32.03%)取食,且偏好粗壮、高大的树木;在取食样方尺度中,黑啄木鸟偏好在有林窗(92.16%)的天然林(96.73%)中取食,偏好郁闭度较低、优势乔木均高较低、优势乔木平均胸径较大、样方中活立木较少、枯立木、倒木较多和距人为干扰更近的生境中取食,与对照样方呈显著差异(p<0.05)。资源选择函数结果表明,影响黑啄木鸟取食生境偏好的关键因子是取食树树种,次关键因子是枯立木数量、优势乔木均高、取食树高度和倒木数量。 展开更多
关键词 黑啄木鸟 取食生境偏好 阔叶红松林 资源选择函数
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基于“气血和”探析关元穴延缓皮肤衰老的作用
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作者 惠倩倩 童伯瑛 +1 位作者 靖媛 游世晶 《内蒙古中医药》 2024年第5期139-141,共3页
气血作为人体生命活动的最基本物质,对人体各脏腑组织器官起着温煦、防御、气化及营养、滋润的作用。气血充足则筋骨强健,肌肉丰满,面色润泽,反应敏捷,气血失和则百病皆生。关元穴作为任脉腧穴,足三阴、阳明、任脉之会,可补气益血,调理... 气血作为人体生命活动的最基本物质,对人体各脏腑组织器官起着温煦、防御、气化及营养、滋润的作用。气血充足则筋骨强健,肌肉丰满,面色润泽,反应敏捷,气血失和则百病皆生。关元穴作为任脉腧穴,足三阴、阳明、任脉之会,可补气益血,调理冲任,保健强壮。当机体皮肤出现衰老现象时,从调和气血入手,使“气血和”以充分荣养、滋润于皮肤,令皮肤荣润细腻、富有光泽。 展开更多
关键词 气血 关元穴 皮肤衰老
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基于刀具轨迹规划的曲面零件仿真加工研究
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作者 井源 苏红磊 《现代制造技术与装备》 2024年第8期71-74,共4页
数控加工中,刀具轨迹规划直接影响加工效率和质量。为了提高曲面零件在数控加工过程中的表面质量,分析典型刀具轨迹规划方法的优缺点,并以曲面模型为例,合理安排加工工艺、选择数控加工策略,进行仿真加工。粗加工阶段,以加工效率为目标... 数控加工中,刀具轨迹规划直接影响加工效率和质量。为了提高曲面零件在数控加工过程中的表面质量,分析典型刀具轨迹规划方法的优缺点,并以曲面模型为例,合理安排加工工艺、选择数控加工策略,进行仿真加工。粗加工阶段,以加工效率为目标设定工艺参数;半精加工阶段,对比平行精加工和流线精加工效果;精加工阶段,结合最佳切削行距和残留高度计算对仿真进行实验分析,通过程序行数、进给长短、切削时间进行数据分析,结合实际操作技巧对仿真结果进行输出,为曲面类零件数控加工提供参考。 展开更多
关键词 自由曲面 刀具轨迹规划 数控加工 行距 加工效率
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场景视角下的集镇公共空间更新——以新昌县儒岙镇共富风貌驿设计为例
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作者 王天玺 郑军 +3 位作者 叶欣 景远 张昱展 杨占超 《浙江建筑》 2024年第1期76-80,共5页
集镇公共空间是承载镇民日常生产生活的核心空间,也是展现新时代乡镇风貌与共同富裕成果的重要窗口。现从场景营造视角出发,在场地、场所与场景三个维度参照下探索乡镇公共空间更新改造场地价值发掘、人本场所建构、场景活力塑造策略。... 集镇公共空间是承载镇民日常生产生活的核心空间,也是展现新时代乡镇风貌与共同富裕成果的重要窗口。现从场景营造视角出发,在场地、场所与场景三个维度参照下探索乡镇公共空间更新改造场地价值发掘、人本场所建构、场景活力塑造策略。并结合新昌县儒岙镇共富风貌驿设计,系统阐明了更具特色、更有温度的集镇公共空间更新路径,可为当代集镇公共空间更新设计提供有益的思路。 展开更多
关键词 集镇公共空间 旧城更新 共富风貌驿
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金属-有机框架材料在超级电容器中的优势和进展
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作者 卢春宇 井源 +4 位作者 魏晓飞 姚世伟 王智飞 王姝斌 戴昉纳 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2024年第2期1-15,共15页
金属-有机框架(Metal-organic framework,MOF)材料因其出色的比表面积、众多的活性位点、可调的孔径范围和灵活的框架结构,在气体分离、储能和催化等领域发挥着重要的作用.近年来,采用高表面积、永久孔隙以及包含固有的氧化还原活性位点... 金属-有机框架(Metal-organic framework,MOF)材料因其出色的比表面积、众多的活性位点、可调的孔径范围和灵活的框架结构,在气体分离、储能和催化等领域发挥着重要的作用.近年来,采用高表面积、永久孔隙以及包含固有的氧化还原活性位点的MOF材料作为超级电容器的电极材料引起了研究者们的关注.本文主要从MOF在超级电容器领域的研究出发,着重介绍了其性能和结构对超级电容器电化学性能的影响,阐述了关于MOF性能调控和结构设计的研究进展.首先,MOF的电导率是影响超级电容器能量密度和功率密度的一大关键性能,而其材料的特殊结构又直接影响了导电率.其次,MOF丰富的活性位点和可调的孔径尺寸等特点都为其导电性能的提升创造了条件.此外,MOF的结构稳定性与超级电容器的循环性能密切相关,稳定结构的构建是增强超级电容器循环性能的重要前提.最后,对MOF未来在超级电容器领域中的研究进行了展望,结构的调控仍然是这一领域的重要研究方向. 展开更多
关键词 金属-有机框架材料 超级电容器 导电率 稳定性 结构调控
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Design,progress and challenges of 3D carbon-based thermally conductive networks
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作者 jing yuan LIU Han-qing +2 位作者 ZHOU Feng DAI Fang-na WU Zhong-shuai 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期844-871,共28页
The advent of the 5G era has stimulated the rapid development of high power electronics with dense integration.Three-dimensional(3D)thermally conductive networks,possessing high thermal and electrical conductivities a... The advent of the 5G era has stimulated the rapid development of high power electronics with dense integration.Three-dimensional(3D)thermally conductive networks,possessing high thermal and electrical conductivities and many different structures,are regarded as key materials to improve the performance of electronic devices.We provide a critical overview of carbonbased 3D thermally conductive networks,emphasizing their preparation-structure-property relationships and their applications in different scenarios.A detailed discussion of the microscopic principles of thermal conductivity is provided,which is crucial for increasing it.This is followed by an in-depth account of the construction of 3D networks using different carbon materials,such as graphene,carbon foam,and carbon nanotubes.Techniques for the assembly of two-dimensional graphene into 3D networks and their effects on thermal conductivity are emphasized.Finally,the existing challenges and future prospects for 3D carbon-based thermally conductive networks are discussed. 展开更多
关键词 Carbon material 3D network GRAPHENE Thermal conductivity Heat transfer
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Diverse foraging strategies of breeding Swinhoe's Storm-petrel in the productive marginal sea of the Northwest Pacific
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作者 Yachang Cheng Lei Zhu +6 位作者 Lin Xue Shisheng Ma Nan Jia Shaoping Zang Zhihai Cao jing yuan Yang Liu 《Avian Research》 SCIE CSCD 2024年第1期27-34,共8页
Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to... Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to maximize energy gains and cope with the intensified challenges of parenting and self-maintenance.Such tradeoff may stem from the heterogeneity of food resources and the constraints of central place foraging.Nevertheless,abundant marine productivity could alleviate the energy limitation for seabirds,resulting in a consistent foraging approach.Here,we investigated the foraging strategy during the breeding season of a cryptic small-sized seabird,Swinhoe’s Storm-petrel(Hydrobates monorhis),in the Yellow Sea,a productive marginal sea of the Northwest Pacific.Using GPS tracking,we evaluated habitat preference,quantified the foraging strategy,and tested if environmental conditions and individual traits influence foraging trips.We found that Swinhoe’s Storm-petrels preferred nearshore areas with shallow water and engaged in primarily short foraging trips.Distinctive southeastward and southwestward strategies emerged when combining trip metrics,including foraging direction,duration,and maximum distance.The bathymetry,proximity to the coastline,and sea surface temperature differed in two foraging strategies.Foraging strategies exhibited flexibility between individuals,potentially explained by wing morphology,in which longer-winged birds are more likely to embark on longer-distance foraging trips.These findings highlight the impact of environmental factors and individual traits on seabirds’foraging decisions in productive marginal sea ecosystems.Our study also provides valuable insights into the foraging ecology of this Asian endemic storm-petrel. 展开更多
关键词 Behavioral strategy BIOLOGGING Central place foraging Marine primary productivity Seabird Sea surface temperature
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