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Characteristics of PM_(2.5) pollution in Beijing after the improvement of air quality 被引量:16
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作者 Xiaojuan Huang Guiqian Tang +9 位作者 Junke Zhang Baoxian Liu Chao Liu Jin Zhang Leilei Cong Mengtian Cheng Guangxuan Yan Wenkang Gao Yinghong Wang Yuesi Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第2期1-10,共10页
Following the implementation of the strictest clean air policies to date in Beijing,the physicochemical characteristics and sources of PM_(2.5) have changed over the past few years.To improve pollution reduction polic... Following the implementation of the strictest clean air policies to date in Beijing,the physicochemical characteristics and sources of PM_(2.5) have changed over the past few years.To improve pollution reduction policies and subsequent air quality further,it is necessary to explore the changes in PM_(2.5) over time.In this study,over one year(2017-2018)field study based on filter sampling(TH-150C;Wuhan Tianhong,China)was conducted in Fengtai District,Beijing,revealed that the annual average PM_(2.5) concentration(64.8±43.1μg/m^3)was significantly lower than in previous years and the highest PM_(2.5) concentration occurred in spring(84.4±59.9μg/m^3).Secondary nitrate was the largest source and accounted for 25.7%of the measured PM_(2.5).Vehicular emission,the second largest source(17.6%),deserves more attention when considering the increase in the number of motor vehicles and its contribution to gaseous pollutants.In addition,the contribution from coal combustion to PM_(2.5) decreased significantly.During weekends,the contribution from EC and NO3−increased whereas the contributions from SO4^2−,OM,and trace elements decreased,compared with weekdays.During the period of residential heating,PM_(2.5) mass decreased by 23.1%,compared with non-heating period,while the contributions from coal combustion and vehicular emission,and related species increased.With the aggravation of pollution,the contribution of vehicular emission and secondary sulfate increased and then decreased,while the contribution of NO3−and secondary nitrate continued to increase,and accounted for 34.0%and 57.5%of the PM_(2.5) during the heavily polluted days,respectively. 展开更多
关键词 PM_(2.5) Seasonal variations Chemical composition Source apportionment Pollution evolution
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基于自适应阻抗的构网型储能变流器控制策略研究 被引量:2
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作者 崔杰 李国庆 +4 位作者 武立国 杨政厚 左希礼 姜自国 朱耿峰 《电气应用》 2025年第1期14-21,共8页
构网型储能变流器因具备调频调峰、削峰填谷及提高电力系统支撑等能力,已成为构建新型电力系统的重要设备之一。围绕构网型储能变流器接入电网时的稳定性展开研究。首先建立了构网型储能变流器接入电网时的数学模型,分析了在不同阻抗特... 构网型储能变流器因具备调频调峰、削峰填谷及提高电力系统支撑等能力,已成为构建新型电力系统的重要设备之一。围绕构网型储能变流器接入电网时的稳定性展开研究。首先建立了构网型储能变流器接入电网时的数学模型,分析了在不同阻抗特性下对并网稳定性的影响。研究结果表明构网型储能变流器采用传统虚拟同步控制,当输出阻抗发生变化以及并离网切换时,容易引起系统振荡,不利于实现无缝切换。针对上述问题在传统虚拟同步控制的基础上加入了自适应阻抗控制,通过仿真验证,该控制策略可以实现不同电网工况下的阻抗适配以及并离网的无缝切换,有效提升了并网系统的稳定性。 展开更多
关键词 构网型储能变流器 自适应阻抗 虚拟同步控制 无缝切换
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自修复密实型防水混凝土施工技术研究及应用 被引量:1
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作者 李明伟 王军 +2 位作者 沈意 李晓伟 李昊宸 《工程建设与设计》 2025年第11期192-195,共4页
针对自修复密实型防水混凝土施工技术的复杂性,依托某建筑工程,分析了自修复密实型防水混凝土的基本原理,对材料选择与配比、施工工艺及质量控制措施进行改进。通过自修复率、孔隙度等指标对研究提出的施工技术进行有效性验证。结果表明... 针对自修复密实型防水混凝土施工技术的复杂性,依托某建筑工程,分析了自修复密实型防水混凝土的基本原理,对材料选择与配比、施工工艺及质量控制措施进行改进。通过自修复率、孔隙度等指标对研究提出的施工技术进行有效性验证。结果表明,在论文提出的材料选择与配比优化下,自修复率为4.13%~5.86%;在施工工艺与质量控制优化下,自修复率及孔隙率分别为80.48%~92.49%和1.24%~2.69%。 展开更多
关键词 防水混凝土 施工工艺 质量控制 自修复性
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Restoration of hydrocarbon generation potential of the highly mature Lower Cambrian Yuertusi Formation source rocks in the Tarim Basin 被引量:2
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作者 Yao Hu Cheng-Zao Jia +6 位作者 Jun-Qing Chen Xiong-Qi Pang Lin Jiang Chen-Xi Wang Hui-Yi Xiao Cai-Jun Li Yu-Jie Jin 《Petroleum Science》 2025年第2期588-606,共19页
The Early Cambrian Yuertusi Formation(Є_(1)y)in the Tarim Basin of China deposits a continuously developed suite of organic-rich black mudstones,which constitute an important source of oil and gas reservoirs in the Pa... The Early Cambrian Yuertusi Formation(Є_(1)y)in the Tarim Basin of China deposits a continuously developed suite of organic-rich black mudstones,which constitute an important source of oil and gas reservoirs in the Paleozoic.However,its hydrocarbon generation and evolution characteristics and resource potential have long been constrained by deeply buried strata and previous research.In this paper,based on the newly obtained ultra-deep well drilling data,the hydrocarbon generation and expulsion model ofЄ_(1)y shale was established by using data-driven Monte Carlo simulation,upon which the hydrocarbon generation,expulsion,and retention amounts were calculated by using the diagenetic method.The research indicates that theЄ_(1)y shale reaches the hydrocarbon generation and expulsion threshold at equivalent vitrinite reflectances of 0.46%and 0.72%,respectively.The cumulative hydrocarbon generation is 68.88×10^(10)t,the cumulative hydrocarbon expulsion is 35.59×10^(10)t,and the cumulative residual hydrocarbon is 33.29×10^(10)t.This paper systematically and quantitatively calculates the hydrocarbon expulsion at various key geological periods for theЄ_(1)y source rocks in the study area for the first time,more precisely confirming that the black shale of theЄ_(1)y is the most significant source rock contributing to the marine oil and gas resources in the Tarim Basin,filling the gap in hydrocarbon expulsion calculation in the study area,and providing an important basis for the formation and distribution of Paleozoic hydrocarbon reservoirs.The prospect of deep ultra-deep oil and gas exploration in the Tarim Basin is promising.Especially,the large area of dolomite reservoirs under the Cambrian salt and source rock interiors are the key breakthrough targets for the next exploration in the Tarim Basin. 展开更多
关键词 Evaluation of resource potential Highly mature hydrocarbon source rocks Yuertusi formation Tarim Basin
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医学生生命教育与健康教育比较研究
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作者 王钰龙 张懿 《叙事医学》 2025年第3期172-180,共9页
生命教育和健康教育对于提升医学生的生命意义感、强化医学生的健康素养、改善医患关系与促进健康中国建设等具有重要意义。医学生的生命教育和健康教育,二者在理论基础、主体内容、实施现状、践行方式等方面,既蕴含共性,也存有个性。... 生命教育和健康教育对于提升医学生的生命意义感、强化医学生的健康素养、改善医患关系与促进健康中国建设等具有重要意义。医学生的生命教育和健康教育,二者在理论基础、主体内容、实施现状、践行方式等方面,既蕴含共性,也存有个性。在对比研究中,凝练总结二者在具体操作过程中尚存的问题和亟需改进的方面,能够为进一步开展医学生生命教育和健康教育提供有针对性的建议。 展开更多
关键词 医学生教育 生命教育 健康教育 比较研究
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选矿工艺流程及改进措施的探讨
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作者 初玉兰 《世界有色金属》 2025年第13期118-120,共3页
金矿作为一种重要的矿产资源,其选矿工艺流程的优化对于提高资源利用效率、降低生产成本具有重要意义。本文介绍了金矿选矿工艺流程的基本环节,分析了当前流程存在的问题,并针对性地提出了一系列改进措施。这些措施包括优化破碎筛分工... 金矿作为一种重要的矿产资源,其选矿工艺流程的优化对于提高资源利用效率、降低生产成本具有重要意义。本文介绍了金矿选矿工艺流程的基本环节,分析了当前流程存在的问题,并针对性地提出了一系列改进措施。这些措施包括优化破碎筛分工艺、改进浮选工艺、强化氰化浸出工艺、加强尾矿环保处理等,旨在提高金矿的综合回收率,实现资源的高效清洁利用。本文的研究对于指导金矿选矿工艺流程的优化实践具有一定的参考价值。 展开更多
关键词 金矿 选矿工艺 工艺流程 改进措施
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黄金矿山急倾斜薄矿脉开采技术研究
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作者 刘广泷 《世界有色金属》 2025年第11期136-138,共3页
在现代化社会经济发展背景下,我国矿产行业获得了良好的发展机遇,同时推动了黄金矿山开采事业的发展。当前,我国正在开采的黄金矿山中,多数属于急倾斜薄矿脉,该类矿体的赋存条件较为复杂,且具有明显的不可改变性。基于此,需要结合实际情... 在现代化社会经济发展背景下,我国矿产行业获得了良好的发展机遇,同时推动了黄金矿山开采事业的发展。当前,我国正在开采的黄金矿山中,多数属于急倾斜薄矿脉,该类矿体的赋存条件较为复杂,且具有明显的不可改变性。基于此,需要结合实际情况,对黄金矿山急倾斜薄矿脉的开采特征进行分析,并对开采现状进行研究,提出可行性的采矿技术,优化开采工艺,强化岩金开采管理,保障黄金矿山开采效率和质量的提升。 展开更多
关键词 黄金矿山 急倾斜 薄矿脉 开采技术
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基于风洞实验室的大跨度钢结构屋面施工技术研究
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作者 李晓伟 闫鹏 +2 位作者 王延镇 玄铁兴 许圆昌 《工程建设与设计》 2025年第11期196-199,共4页
针对风洞实验室现场场地狭小,难以选择合适的吊装机械进行施工等问题,研究选择在大跨度钢结构的南侧进行吊装。根据结构特点,将屋面桁架杆件散件发至现场,并在现场进行拼装组合成整榀桁架用以解决上述问题。结果显示,吊索额定工作载荷为... 针对风洞实验室现场场地狭小,难以选择合适的吊装机械进行施工等问题,研究选择在大跨度钢结构的南侧进行吊装。根据结构特点,将屋面桁架杆件散件发至现场,并在现场进行拼装组合成整榀桁架用以解决上述问题。结果显示,吊索额定工作载荷为57.9 t,地基承载力为150 kPa,满足项目要求。研究结果可应用于大跨度钢结构屋面在公共建筑等领域的施工技术中,保障了施工的安全。 展开更多
关键词 风洞实验室 吊装机械 钢结构 屋面桁架杆
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高效液相色谱法检测丹田降脂丸中3种活性成分的含量
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作者 王丹 张静 许保海 《分析仪器》 2025年第6期41-45,共5页
建立了高效液相色谱法检测丹田降脂丸中2,3,5,4-四羟基二苯乙烯-2-O-β-D-葡萄糖苷(下称葡萄糖苷)、23-乙酰泽泻醇B和淫羊藿苷成分含量的检测方法。Capcell Pak UG C18色谱柱分离;检测波长:葡萄糖苷、23-乙酰泽泻醇B和淫羊藿苷检测波长... 建立了高效液相色谱法检测丹田降脂丸中2,3,5,4-四羟基二苯乙烯-2-O-β-D-葡萄糖苷(下称葡萄糖苷)、23-乙酰泽泻醇B和淫羊藿苷成分含量的检测方法。Capcell Pak UG C18色谱柱分离;检测波长:葡萄糖苷、23-乙酰泽泻醇B和淫羊藿苷检测波长分别设定319nm、208nm和271nm;柱温:28℃;进样体积:10μL;以乙腈为流动相A,1.0%磷酸溶液为流动相B,梯度洗脱,洗脱方法:0~5min 13%A,5~15min 13%~45%A,15~24min 45%~86%A,24~30min 86%A,30~35min 13%A,外标法定量。结果表明,葡萄糖苷、23-乙酰泽泻醇B和淫羊藿苷在0.1896~18.96、0.0983~9.83和0.0981~9.81μg/mL范围内线性良好;平均回收率分别为99.2%、99.5%和99.7%;方法重复性RSD(n=6)在5.0%以内;供试品溶液在24h内稳定。该方法检测时间短、操作简单,可以用于丹田降脂丸的质量控制。 展开更多
关键词 高效液相色谱法 丹田降脂丸 活性成分
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全地下式污水处理厂箱体结构与基坑支护的结合设计
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作者 庄修伟 郝凤平 《特种结构》 2025年第5期36-41,共6页
对于全地下式污水处理厂工程,由于埋深较深且面积较大,基坑支护设计和箱体结构抗浮设计都是必不可少的。在以往工程中,基坑支护通常作为临时性措施,与箱体结构分别单独设计。如何将箱体结构与基坑支护有效结合设计,使整个工程方案更加... 对于全地下式污水处理厂工程,由于埋深较深且面积较大,基坑支护设计和箱体结构抗浮设计都是必不可少的。在以往工程中,基坑支护通常作为临时性措施,与箱体结构分别单独设计。如何将箱体结构与基坑支护有效结合设计,使整个工程方案更加合理经济是需要进一步考虑的重点难点。全文依照福州某全地下式污水处理厂工程实例,结合周边环境、工程地质、水文、建设需求等因素,对包括箱体结构、基坑支护、箱体结构抗浮和地基处理等设计要点进行详细解析,特别是将箱体结构与基坑支护结构通过连接联合抗浮的设计方法,安全可靠且经济环保,为以后的地下式污水处理厂设计提供一种思路作为借鉴。 展开更多
关键词 箱体结构 基坑支护 结合设计
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‘脐红’猕猴桃组培再生和遗传转化体系建立与优化
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作者 徐长彬 李林 +5 位作者 方志蒙 缪星茹 祝小水 雷长生 孙学鹏 胡校粒 《浙江林业科技》 2025年第2期64-70,共7页
以‘脐红’猕猴桃Actinidia chinensis‘Qihong’无菌苗的叶片为外植体,探究不同浓度植物生长调节剂组合对猕猴桃愈伤组织诱导及再生的影响,筛选出‘脐红’猕猴桃叶片离体再生体系的最佳配方,并利用根癌农杆菌介导的叶盘法将AcALKBH4超... 以‘脐红’猕猴桃Actinidia chinensis‘Qihong’无菌苗的叶片为外植体,探究不同浓度植物生长调节剂组合对猕猴桃愈伤组织诱导及再生的影响,筛选出‘脐红’猕猴桃叶片离体再生体系的最佳配方,并利用根癌农杆菌介导的叶盘法将AcALKBH4超表达载体转入‘脐红’猕猴桃,通过实时荧光定量PCR鉴定出阳性材料,成功通过该体系快速获得转基因植株。结果表明:培养基配方为MS(4.43 g·L^(−1))+蔗糖(30 g·L^(−1))+6-BA(2.0 mg·L^(−1))+NAA(0.5 mg·L^(−1))+TDZ(1.0 mg·L^(−1))+琼脂(8 g·L^(−1))最有利于‘脐红’猕猴桃叶片愈伤组织的诱导和生长,诱导率达85.2%;培养基配方为MS(4.43 g·L^(−1))+蔗糖(30 g·L^(−1))+6-BA(1.0 mg·L^(−1))+NAA(0.1 mg·L^(−1))+琼脂(8 g·L^(−1))时,培养5~6周后,‘脐红’猕猴桃愈伤组织再生出芽率最高可达60.0%。继续培养新生芽,长出叶片后进行转基因阳性植株检测,阳性率为25.0%~30.0%。 展开更多
关键词 猕猴桃 愈伤组织 芽诱导 再生 遗传转化
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Characteristics and life cycle carbon emission reduction potential of waste recycling after implementing new waste classification policy in China:From case study to national perspective
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作者 Hao Fu Le Chen +4 位作者 Wei Fang Wenfang Gao Kun Hu Panyue Zhang Guangming Zhang 《Journal of Environmental Sciences》 2025年第9期645-657,共13页
Under the background of resource shortage and global warming,it is of great significance to explore the status,influencing factors and carbon emission reduction effect of waste recycling in China after the implementat... Under the background of resource shortage and global warming,it is of great significance to explore the status,influencing factors and carbon emission reduction effect of waste recycling in China after the implementation of new waste classification policy for guiding waste classification and carbon emission accounting.In this research,the temporal and spatial changes and influencing factors of waste recycling were studied from subdistrict level,life-cycle carbon emission reduction was predicted and policy suggestions for waste recycling were proposed.The results showed that after the implementation of new waste classification policy,the amount of recycled waste and the proportion of low-value recycled waste increased by 420.93 t and 2.29%per month on average,respectively.The district center has the largest amount of recycled waste.Income was the main factors affecting waste recycling,and online shopping and takeout could become important sources of recyclable waste.Accounting cradle-to-grave life cycle carbon footprint,waste plastics takes up the most contribution,accounting for 39.11%,and nearly 391.68 Mt CO_(2eq) would be reduced by waste recycling in China by 2030.Therefore,in the process of waste classification,refining waste classification to increase the amount of low-value recyclables,and rationally deploying collection and transportation vehicles to ensure efficient waste recycling are of great significance to achieve the goal of“carbon peaking and carbon neutrality”. 展开更多
关键词 Waste classification Recyclable waste Life cycle carbon footprint Carbon emission reduction Policy suggestions
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The epidemiological landscape of lung cancer:current status,temporal trend and future projections based on the latest estimates from GLOBOCAN 2022
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作者 Yuting Ji Yunmeng Zhang +7 位作者 Siwen Liu Jingjing Li Qianyun Jin Jie Wu Hongyuan Duan Xiaomin Liu Lei Yang Yubei Huang 《Journal of the National Cancer Center》 2025年第3期278-286,共9页
Background Given the relatively unfavorable prognosis and significant geographic differences in lung cancer burden,it is critical to update the global landscape of lung cancer to inform local strategies.Methods Based ... Background Given the relatively unfavorable prognosis and significant geographic differences in lung cancer burden,it is critical to update the global landscape of lung cancer to inform local strategies.Methods Based on the GLOBOCAN 2022,the age-standardized incidence rate(ASIR)and mortality rate(ASMR)were compared and linked to the Human Development Index(HDI)across different populations.The temporal trends in ASIR/ASMR were characterized as estimated annual percentage change(EAPC),and demographic projections were performed up to 2050.Results Globally,an estimated 2,480,675 cases and 1,817,469 deaths from lung cancer occurred in 2022.Both ASIR and ASMR of lung cancer varied widely by world region,with ASIR ranging from 2.06 to 39.38 per 100,000 and ASMR from 1.95 to 31.70 per 100,000.China alone accounted for>40%of cases and deaths worldwide.Both ASIR and ARMR of lung cancer increased with HDI(R2:0.54 and 0.47,all P values<0.001),regardless of gender.Based on available data,both ASIR during 2001–2010 and ASMR during 2001–2015 showed decreasing trends in males(EAPC:1.50%and−2.22%)but increasing trends in females(EAPC:1.08%and 0.07%).Similar trends in ASIR and ASMR were observed among the elder population(≥50 years);however,downward trends were observed in the younger population(<50 years).Alongside the aging and growth of the population,estimated cases and deaths from overall lung cancer would increase by 86.2%and 95.2%up to 2050 as compared with estimates in 2022,respectively.Notably,increased early-onset lung cancer was only observed in transitioning countries,while decreased early-onset lung cancer was observed in transitioned countries.Conclusion Lung cancer maintained as the leading cancer burden worldwide.Unless timely preventive interventions in tobacco mitigation,early screening,and precise treatment,the global lung cancer burden is expected to increase in the future,especially for transitioning countries. 展开更多
关键词 Lung cancerinc idence MORTALITY temporal trend HDI
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Sequence stratigraphy analysis and lithofacies paleogeography reconstruction of isolated platform in a rift lake basin:Implications for deepwater hydrocarbon exploration in the subsalt of Santos Basin,Brazil
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作者 HUANG Jixin WANG Hongjun +7 位作者 XU Fang YANG Mengying ZHAO Junfeng LI Peijia LI Chenqing LIU Zeqiang XIONG Ying TAN Xiucheng 《Petroleum Exploration and Development》 2025年第4期982-1000,共19页
By integrating core observations,logging data and seismic interpretation,this study takes the massive Cretaceous carbonates in the M block of the Santos Basin,Brazil,as an example to establish the sequence filling pat... By integrating core observations,logging data and seismic interpretation,this study takes the massive Cretaceous carbonates in the M block of the Santos Basin,Brazil,as an example to establish the sequence filling pattern of fault-bounded isolated platforms in rift lake basins,reveal the control mechanisms of shoal-body development and reservoir formation,and reconstruct the evolutionary history of lithofacies paleogeography.The following results are obtained.(1)Three tertiary sequences(SQ1-SQ3)are identified in the Lower Cretaceous Itapema-Barra Velha of the M block.During the depositional period of SQ1,the rift basement faults controlled the stratigraphic distribution pattern of thick on both sides and thin in the middle.The strata overlapped to uplift in the early stage.During the depositional period of SQ2-SQ3,the synsedimentary faults controlled the paleogeomorphic reworking process with subsidence in the northwest and uplifting in the northeast,accompanied with the relative fall of lake level.(2)The Lower Cretaceous in the M block was deposited in a littoral-shallow lake,with the lithofacies paleogeographic pattern transiting from the inner clastic shoals and outer shelly shoals in SQ1 to the alternation of mounds and shoals in SQ2-SQ3.(3)Under the joint control of relative lake-level fluctuation,synsedimentary faults and volcanic activity,the shelly shoals in SQ1 tend to accumulated vertically in the raised area,and the mound-shoal complex in SQ2-SQ3 tends to migrate laterally towards the slope-break belt due to the reduction of accommodation space.(4)The evolution pattern of high-energy mounds and shoals,which were vertically accumulated in the early stage and laterally migrated in the later stage,controlled the transformation of high-quality reservoirs from“centralized”to“ring shaped”distribution.The research findings clarify the sedimentary patterns of mounds and shoals and the distribution of favorable reservoirs in the fault-controlled lacustrine isolated platform,providing support for the deepwater hydrocarbon exploration in the subsalt carbonate rocks in the Santos Basin. 展开更多
关键词 lacustrine carbonate fault-bounded isolated platform sedimentary pattern sequence lithofacies paleogeography Cretaceous Itapema-Barra Velha Santos Basin
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Phase behavior of CO_(2)-shale oil in nanopores
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作者 WANG Yuhan LEI Zhengdong +6 位作者 LIU Yishan PAN Xiuxiu CHEN Zhewei ZHANG Yuanqing ZHENG Xiaoyu LIU Pengcheng HAN Yi 《Petroleum Exploration and Development》 2025年第1期182-195,共14页
Considering the interactions between fluid molecules and pore walls,variations in critical properties,capillary forces,and the influence of the adsorbed phase,this study investigates the phase behavior of the CO_(2)-s... Considering the interactions between fluid molecules and pore walls,variations in critical properties,capillary forces,and the influence of the adsorbed phase,this study investigates the phase behavior of the CO_(2)-shale oil within nanopores by utilizing a modified Peng-Robinson(PR)equation of state alongside a three-phase(gas-liquid-adsorbed)equilibrium calculation method.The results reveal that nano-confinement effects of the pores lead to a decrease in both critical temperature and critical pressure of fluids as pore size diminishes.Specifically,CO_(2) acts to inhibit the reduction of the critical temperature of the system while promoting the decrease in critical pressure.Furthermore,an increase in the mole fraction of CO_(2) causes the critical point of the system to shift leftward and reduces the area of the phase envelope.In the shale reservoirs of Block A in Gulong of the Daqing Oilfield,China,pronounced confinement effects are observed.At a pore diameter of 10 nm,reservoir fluids progressively exhibit characteristics typical of condensate gas reservoirs.Notably,the CO_(2) content in liquid in 10 nm pores increases by 20.0%compared to that in 100 nm pores,while the CO_(2) content in gas decreases by 10.8%.These findings indicate that confinement effects enhance CO_(2) mass transfer within nanopores,thereby facilitating CO_(2) sequestration and improving microscopic oil recovery. 展开更多
关键词 shale oil NANOPORES nano-confinement effect phase behavior PR equation of state
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Compound extreme events and health risks in China:A review
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作者 Haosu Tang Gang Huang +3 位作者 Kaiming Hu Jun Wang Cunrui Huang Xianke Yang 《Atmospheric and Oceanic Science Letters》 2025年第5期54-64,共11页
Against the backdrop of global warming,China has been facing increasingly frequent and severe extreme weather and climate events,with a prominent risk of compound extreme events induced by interactions among multiple ... Against the backdrop of global warming,China has been facing increasingly frequent and severe extreme weather and climate events,with a prominent risk of compound extreme events induced by interactions among multiple climate drivers and/or hazards.The present study first reviews the definition and classification of compound extreme events in China.Then,it summarizes research progress on the evolutionary characteristics,formation mechanisms,and future projections of different types of compound extreme events.The potential risks and possible impact pathways of three specific event types—namely,continuous day–night hot extremes,temperature–humidity compound events,and high-temperature–ozone compound events—on the health of the Chinese population are then explored.Finally,a framework for assessing the hazard risk of compound extreme events is constructed,accompanied by response strategies based on carbon neutrality targets.Building on existing research achievements,five future research directions are proposed:(1)identifying the risk chains of compound events;(2)addressing the constraints of observational records and coupled model performances;(3)attributing and understanding the drivers of compound extreme events;(4)finding optimal pathways for carbon reduction and air quality improvement;and(5)promoting inter-disciplinary,multi-regional,and cross-sectoral collaboration.Strengthening research in these directions will deepen our understanding of compound extreme events and provide technological support for climate change adaptation and health risk responses in China. 展开更多
关键词 Global warming Extreme weather Compound extreme event Air pollution Population health Carbon neutrality
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An Efficient Anti-Quantum Blind Signature with Forward Security for Blockchain-Enabled Internet of Medical Things
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作者 Gang Xu Xinyu Fan +4 位作者 Xiu-Bo Chen Xin Liu Zongpeng Li Yanhui Mao Kejia Zhang 《Computers, Materials & Continua》 2025年第2期2293-2309,共17页
Blockchain-enabled Internet of Medical Things (BIoMT) has attracted significant attention from academia and healthcare organizations. However, the large amount of medical data involved in BIoMT has also raised concern... Blockchain-enabled Internet of Medical Things (BIoMT) has attracted significant attention from academia and healthcare organizations. However, the large amount of medical data involved in BIoMT has also raised concerns about data security and personal privacy protection. To alleviate these concerns, blind signature technology has emerged as an effective method to solve blindness and unforgeability. Unfortunately, most existing blind signature schemes suffer from the security risk of key leakage. In addition, traditional blind signature schemes are also vulnerable to quantum computing attacks. Therefore, it remains a crucial and ongoing challenge to explore the construction of key-secure, quantum-resistant blind signatures. In this paper, we introduce lattice-based forward-secure blind signature (LFSBS), a lattice-based forward-secure blind signature scheme for medical privacy preservation in BIoMT. LFSBS achieves forward security by constructing a key evolution mechanism using a binary tree structure. This mechanism ensures that even if future encryption keys are leaked, past data can still remain secure. Meanwhile, LFSBS realizes post-quantum security based on the hardness assumption of small integer solution (SIS), making it resistant to potential quantum computing attacks. In addition, we formally define and prove the security of LFSBS in a random oracle model, including blindness and forward-secure unforgeability. Comprehensive performance evaluation shows that LFSBS performs well in terms of computational overhead, with a reduction of 22%–73% compared to previous schemes. 展开更多
关键词 Internet of Things blockchain forward-secure blind signature
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泻肺利水合剂联合西医常规方法治疗慢性缺血性心力衰竭气虚血瘀证疗效的真实世界、多中心、队列研究 被引量:25
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作者 来晓磊 尚菊菊 +3 位作者 刘红旭 佟彤 邢文龙 李享 《中医杂志》 CSCD 北大核心 2022年第6期544-550,共7页
目的探讨泻肺利水合剂联合西医常规方法治疗慢性缺血性心力衰竭气虚血瘀证的临床疗效。方法纳入8家协作医院因慢性缺血性心力衰竭气虚血瘀证住院患者,依据患者意愿分为泻肺利水合剂组73例及辨证施治组72例。所有患者均给予西医规范化治... 目的探讨泻肺利水合剂联合西医常规方法治疗慢性缺血性心力衰竭气虚血瘀证的临床疗效。方法纳入8家协作医院因慢性缺血性心力衰竭气虚血瘀证住院患者,依据患者意愿分为泻肺利水合剂组73例及辨证施治组72例。所有患者均给予西医规范化治疗,在此基础上泻肺利水合剂组给予泻肺利水合剂,辨证施治组由临床应诊医师根据个人经验依辨证施治原则处方。两组患者均每日1剂口服,疗程(14±3)天。治疗前后比较患者血清N端脑钠肽前体(NT-proBNP)水平、NT-proBNP下降幅度、临床症状积分(包括喘息、气短、神疲乏力、肢体浮肿、小便短少)、心功能[包括左室舒张末期内径(LVEDD)、左室射血分数(LVEF)]、6分钟步行距离,记录患者治疗期间不良反应;治疗结束30天及180天随访记录主要心血管不良事件(MACE)发生情况。结果两组治疗后NT-proBNP水平均较本组治疗前下降,治疗后泻肺利水合剂组NT-proBNP水平低于辨证施治组,泻肺利水合剂组NT-proBNP下降(1920±1115.49)pg/ml,大于辨证施治组的下降值(1273±120.81)pg/ml(P<0.05)。治疗后泻肺利水合剂组LVEDD水平较治疗前下降,LVEF水平较治疗前上升(P<0.05)。两组患者6分钟步行试验距离均较治疗前增加、各项临床症状积分均较治疗前下降,且泻肺利水合剂组6分钟步行距离大于辨证施治组,气短、肢体浮肿、小便短少症状积分低于辨证施治组(P<0.05)。治疗后结束30天及180天随访时两组MACE发生情况差异无统计学意义(P>0.05)。两组均未见明显不良反应。结论在联合西医常规疗法基础上,泻肺利水合剂较常规中药辨证治疗可以更好地降低慢性缺血性心力衰竭气虚血瘀证患者血清NT-proBNP水平、改善患者临床症状与心功能、延长6分钟步行距离,且安全性好。 展开更多
关键词 慢性缺血性心力衰竭 泻肺利水合剂 气虚血瘀证 N端脑钠肽前体 6分钟步行距离 真实世界研究 队列研究
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四川盆地磨溪地区灯四段风化壳岩溶储层特征 被引量:9
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作者 杨帆 刘立峰 +3 位作者 冉启全 孔金平 黄苏琦 黄昌武 《岩性油气藏》 CSCD 北大核心 2020年第2期43-53,共11页
近年来,四川盆地磨溪地区灯四段的油气勘探取得了重大突破,为研究磨溪22井区灯四上亚段优质岩溶储层特征及分布规律,开展了岩心分析、物性测试、地震资料解释、测井分析和有利岩溶储层发育区预测等工作。结果表明:①岩溶储层的岩性主要... 近年来,四川盆地磨溪地区灯四段的油气勘探取得了重大突破,为研究磨溪22井区灯四上亚段优质岩溶储层特征及分布规律,开展了岩心分析、物性测试、地震资料解释、测井分析和有利岩溶储层发育区预测等工作。结果表明:①岩溶储层的岩性主要为藻云岩类、砂屑云岩类和结晶云岩类,储集空间主要为溶蚀孔、溶洞和裂缝;②溶蚀作用包括同生期大气淡水的溶蚀作用、埋藏期深部热液溶蚀作用和有机酸的溶蚀作用、表生期大气淡水的溶蚀作用;③表生期的溶蚀作用控制了优质储层的分布,多发育于垂直渗流带附近和水平潜流带上部区域,平面上优质储层的分布受控于沉积相带和古地貌特征,以丘滩相和溶丘斜坡较好。该研究成果为磨溪地区下一步勘探指明了方向。 展开更多
关键词 风化壳 岩溶储层 优质储层 发育特征 灯四上亚段 四川盆地
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不同硫含量石油焦中低温煅烧性能及脱硫机理研究 被引量:5
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作者 高守磊 薛济来 +4 位作者 郎光辉 刘瑞 包崇爱 王志国 张法利 《轻金属》 CSCD 北大核心 2018年第2期37-42,46,共7页
在实验室煅烧炉内对三种不同品种石油焦进行了700~1100℃阶段热处理,并对煅烧后的石油焦真密度、粉末电阻率、Lc值、气孔率等进行了检测分析,同时将煅烧后的石油焦颗粒进行了扫描电镜分析。通过分析研究发现,随着煅烧温度的增加,低硫、... 在实验室煅烧炉内对三种不同品种石油焦进行了700~1100℃阶段热处理,并对煅烧后的石油焦真密度、粉末电阻率、Lc值、气孔率等进行了检测分析,同时将煅烧后的石油焦颗粒进行了扫描电镜分析。通过分析研究发现,随着煅烧温度的增加,低硫、中硫、高硫石油焦TG和DTG曲线、煅烧后的性能、脱硫率、碳晶格的生长、气孔率等区别明显,这可为生产使用这三种类型硫含量的石油焦提供试验依据。 展开更多
关键词 石油焦 中低温煅烧 热重差热 脱硫率 碳晶格Lc 气孔率 扫描电镜
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