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Geochemistry of late Mesozoic lamprophyre dykes from the Taihang Mountains,north china,and implications for the sub-continental lithospheric mantle

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Geochemistry of late Mesozoic lamprophyre dykes from the Tai...

A Strategic Shift from Manufacturing Dominated District to Eco-city, the Case of Shijingshan in beijing

中国科学院地质与地球物理研究所2002学术年会

作者： BIN CHEN~(a,b) &MINGGUO zhai~b a.Department of Geology,Peking University,beijing 100871,china b.Institute of Geology and Geophysics,chinese academy of sciences,beijing 100029,china

Many late Mesozoic lamprophyre dykes occur in the Taihang Mountains(north china).These lamprophyres are rich in large ion lithophile elements(***,Sr,Ba,and K.) and light REE,and have highly differentiated REE *** show large but regular variations in chemical and Nd-Sr isotopic *** these suggest that the lamprophyres were produced from differentiation of a parental magma,coupled with contamination by lower *** parental magma was derived from melting of a long-term enriched sub-continental lithospheric mantle source as is indicated by the highly enriched isotopic signatures of the *** enrichment in the area was probably produced by interaction of volatile-rich melts released from the asthenosphere with the above lithosphere in middle Proterozoic times.

关键词： geochemistry lamprophyres lithosphere Mesozoic northern china

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A Strategic Shift from Manufacturing Dominated District to E...

国际生态城市建设论坛

作者： Baohui zhai Ph.D. candidate Research Center for Eco-environmental sciences chinese academy of sciences 18 Shuangqing Road beijing 100085 P R china

＜正＞ The paper proposes a strategic shift from manufacturing dominated area to an Eco-city, a challenging work for both the government and the academics, based on Shijingshan, western district of beijing proper. It is a big contributor to both air pollution and industrial GDP of beijing. Nevertheless, it is still a under developing area in overall economic development. After examining status quo of the steel complex, a steel museum is initiated along its 5 km long open plant, combined with replanting and grassing its formerly material sites. Besides, a cemetery

关键词： Manufacturing dominated city Eco-city strategic shift greening cemetery culture relics

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煤与天然气协同开采理论与技术构想

煤炭科学技术 2024年第4期52卷 50-68页

作者：杨胜利张燊王旭东张凯辛德林翟瑞昊中国矿业大学(北京)能源与矿业学院北京100083 厚煤层绿色智能开采教育部工程研究中心北京100083 中国矿业大学(北京)内蒙古研究院内蒙古鄂尔多斯017004 神华新街能源有限责任公司内蒙古鄂尔多斯017200 煤炭开采水资源保护与利用全国重点实验室北京102209 中煤科工集团武汉设计研究院有限公司湖北武汉430061

我国存在大量的煤炭与天然气重叠赋存资源,出于对资源开采效率的要求,大量的煤与天然气重叠资源需要在同一时空内同步开采,传统的煤与天然气开采理论与技术难以满足协同开采出现的技术难题,煤与天然气协同开采的进程受到了严重制约。基... 详细信息

我国存在大量的煤炭与天然气重叠赋存资源,出于对资源开采效率的要求,大量的煤与天然气重叠资源需要在同一时空内同步开采,传统的煤与天然气开采理论与技术难以满足协同开采出现的技术难题,煤与天然气协同开采的进程受到了严重制约。基于此,结合国内煤与天然气重叠赋存情况对煤与天然气协同开采进行了科学定义,总结了已有可借鉴的煤与天然气开采技术和相关理论。建立了天然气井近场岩体力学理论、天然气近场围岩耦合损伤理论、“围岩–水泥环–套管”耦合损伤理论、煤与天然气协同开采垂直场围岩耦合损伤理论,揭示了煤与天然气协同开采围岩的耦合损伤机理,为煤与天然气技术体系的构建提供了理论基础。提出了“煤与天然气协同开采技术”“煤炭开采通过废弃井技术”和“天然气近场小煤柱留设技术”3项技术以及“协同开采分区规划系统”“透明地质与生产信息动态监测系统”和“煤与天然气协同区安全监测与评价系统”三大系统,为煤与天然气协同开采提供技术支持,提高煤炭与天然气资源的开采效率。在此基础上,构建了煤与天然气协同开采的理论与技术体系,明确了煤与天然气协同开采未来的研究重点,提出了我国煤与天然气资源安全、绿色、高效协同开采的技术路径与研究方向。

关键词：煤与天然气重叠资源协同开采无人智能化耦合损伤

基于QAR数据的民机高高原进近着陆风险评估方法

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北京航空航天大学学报 2024年第1期50卷 77-85页

作者：陈农田满永政李俊辉中国民用航空飞行学院航空工程学院广汉618307 中国民用航空飞行学院民航安全工程学院广汉618307

民机高高原进近着陆是高原飞行高风险阶段。为有效实施高高原进近着陆风险识别和等级判据,提出基于熵权可变模糊识别的长短时记忆网络与深度神经网络(LSTM-DNN)相融合的深度学习风险评估方法。基于快速存取记录器(QAR)记录的高高原飞行... 详细信息

民机高高原进近着陆是高原飞行高风险阶段。为有效实施高高原进近着陆风险识别和等级判据,提出基于熵权可变模糊识别的长短时记忆网络与深度神经网络(LSTM-DNN)相融合的深度学习风险评估方法。基于快速存取记录器(QAR)记录的高高原飞行数据,借鉴民机飞行品质监控(FOQA)咨询通告和行业QAR监控标准,结合指标重要度分析与Delphi专家调查,提取着陆时航向变化大、航迹低、610~305 m进近时下降率大、接地时垂直加速度及153~15 m进近时下降率大5个关键监控项目作为民机高高原进近着陆风险评估指标。为克服评估指标权重主观性偏差,应用熵权法确定评估指标权重,基于可变模糊识别方法构建风险等级隶属函数,建立基于LSTM-DNN的民机高高原进近着陆风险评估模型。以成都—拉萨进近着陆航段为例,提取QAR数据,对该风险评估模型进行训练与测试,并与Logistic多元回归、支持向量机(SVM)等评估方法进行比较,结果表明:所提方法平均准确率达到94.18%,最高可达94.79%,验证了方法的客观有效性。

关键词：高高原飞行快速存取记录器数据熵权可变模糊识别 LSTM-DNN深度学习风险评估

Radiation-Assisted Synthesis of Crown Ether-Modified Covalent Organic Frameworks for Lithium Isotope Separation

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CCS Chemistry 2024年第10期6卷 2594-2606页

作者： Shouchao Zhong Yue Wang Jianhui Lan Mingshu Xie Yiqian Wu Jiuqiang Li Fujian Liu Lilong Jiang Jing Peng Liyong Yuan Maolin zhai Weiqun Shi Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science Key Laboratory of Polymer Chemistry and Physics of the Ministry of EducationCollege of Chemistry and Molecular EngineeringBeijing National Laboratory for Molecular SciencesPeking UniversityBeijing 100871 National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou350002 Fujian Laboratory of Nuclear Energy Chemistry Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049

γ-ray radiation-induced grafting strategy was first employed to immobilize 4-aminobenzo-15-crown-5 onto a covalent organic framework(COF).This endeavor culminated in the successful synthesis of a class of two-dimensional crown ether-modified COFs(named[15C5]n%-(TzDa-G-x%)),marking the maiden utilization of COFs in the realm of^(6)Li/^(7)Li isotope *** COFs exhibited swifter adsorption kinetics than alternative *** them,[15C5]_(57%)-(TzDa-G-50%)with its excellent crystallinity,porosity,and stability exhibited the best performance in Li+adsorption and^(6)Li/^(7)Li isotope *** Li+adsorption in acetonitrile achieved a capacity of 3.6 mg·g^(−1)within 30 min and a saturation capacity of 7.3 mg·g^(−1).The single-stage separation factor of^(6)Li/^(7)Li isotopes was 1.014±*** results of dynamic adsorption column experiments showed that the packed column made of[15C5]_(57%)-(TzDa-G-50%)maintained stable performance during four cycles of Li+adsorptionelution,with over 99%Li+removal rate in *** crown ether-modified COF has potential application in^(6)Li/^(7)Li isotope separation,and this radiation-assisted synthesis strategy is expected to become universal in the modification of COFs for diverse applications.

关键词： covalent organic framework gamma radiation modification crown ether ^(6)Li/^(7)Li isotope separation adsorption column

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人类学人观视角下四川农区藏族生态观探究

北方民族大学学报（哲学社会科学版） 2024年第2期 67-75页

作者：翟淑平中国社会科学院民族学与人类学研究所北京100081

人观是人类学研究的基础性命题,其核心是关于一个民族对“人”的基本看法,构成了一个民族的宇宙观、时空观、自然观的基础。人类学的人观研究能够为理解藏族生态观提供理论洞见。基于四川农区藏族的田野调查表明,藏族观念世界中自我与... 详细信息

人观是人类学研究的基础性命题,其核心是关于一个民族对“人”的基本看法,构成了一个民族的宇宙观、时空观、自然观的基础。人类学的人观研究能够为理解藏族生态观提供理论洞见。基于四川农区藏族的田野调查表明,藏族观念世界中自我与他者的多重关系,呈现了其整体生活中的人观以及藏族生态观的本质。三界宇宙论对人、神、物整体关系的处理以及藏传佛教的因果论、转世观使人们能够跳出自我,关照多重他者,使人们能够在由人、万物、神灵等构成的宇宙整体中,更全面、深刻地理解生命。“生命”是“生态”本身所应具有的本质意涵。对藏族生态观的研究,应沉潜到生命的本体意义,形成涵括多重主体的德性、世界想象、宇宙论等在内的综合思考。

关键词：人观生态观他者宇宙观

大模型生成回答与人类回答文本的语言特征比较研究

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中文信息学报 2024年第4期38卷 17-27页

作者：朱君辉王梦焰杨尔弘聂锦燃杨麟儿王誉杰北京语言大学国家语言资源监测与研究平面媒体中心北京100083 北京语言大学计算科学学院北京100083 北京交通大学计算机与信息技术学院北京100044

近年,人工智能的语言生成技术突飞猛进,基于自然语言生成技术的聊天机器人ChatGPT能够自如地与人对话、回答问题。为了探究机器生成语言与人类语言的差异,该文分别收集了人类和ChatGPT在中文开放域上3293个问题的回答作为语料,对两种语... 详细信息

近年,人工智能的语言生成技术突飞猛进,基于自然语言生成技术的聊天机器人ChatGPT能够自如地与人对话、回答问题。为了探究机器生成语言与人类语言的差异,该文分别收集了人类和ChatGPT在中文开放域上3293个问题的回答作为语料,对两种语料分别提取并计算描述性特征、字词常用度、字词多样性、句法复杂性、语篇凝聚力五个维度上的161项语言特征,利用分类算法验证用这些特征区别两种语言的有效性,并考察、对比这些特征来阐释人类、机器生成两种语言的异同。研究结果发现,两种文本在描述性特征、字词常用度、字词多样性三个维度的77项语言特征上存在显著差异,相较于机器回答语言,人类回答语言表现出易读性高、论元重叠度低、口语色彩明显、用词丰富多样、互动性强等特点。

关键词： ChatGPT 人类语言语言特征机器学习

Mammalian Cytosolic Thioredoxin Reductase:Redox Potential and Redox Status

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Mammalian Cytosolic Thioredoxin Reductase:Redox Potential an...

IbNIEL-mediated degradation of IbNAC087 regulates jasmonic acid-dependent salt and drought tolerance in sweet potato

第九届全国酶学学术讨论会暨邹承鲁诞辰85周年纪念会

作者： Guanglei zhai Liangwei Zhong College of Life sciences,Graduate University of chinese academy of sciences,YuQuan Road 19(A),beijing 100049

There are three isoenzymes of mammalian thioredoxin reductase (TrxR) i.e. cytosolic,mitochondrial and testis specific TrxR,all of which are homodimers associated in a head-to-tail *** contrast to *** TrxR,mammalian Tr... 详细信息

关键词： thioredoxin reductase trx system redox potential

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Journal of Integrative Plant Biology 2024年第2期66卷 176-195页

作者： Xu Li Zhen Wang Sifan Sun Zhuoru Dai Jun Zhang Wenbin Wang Kui Peng Wenhao Geng Shuanghong Xia Qingchang Liu Hong zhai Shaopei Gao Ning Zhao Feng Tian Huan Zhang Shaozhen He Key Laboratory of Sweet Potato Biology and Biotechnology Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis&Utilization and Joint Laboratory for International Cooperation in Crop Molecular BreedingMinistry of EducationCollege of Agronomy&BiotechnologyChina Agricultural UniversityBeijing 100193China Sanya Institute of china Agricultural University Sanya 572025China State Key Laboratory of Plant Physiology and Biochemistry National Maize Improvement CenterKey Laboratory of Biology and Genetic Improvement of MaizeBeijing Key Laboratory of Crop Genetic ImprovementChina Agricultural UniversityBeijing 100193China

Sweet potato(Ipomoea batatas[L.]Lam.)is a crucial staple and bioenergy *** abiotic stress tolerance holds significant importance in fully utilizing marginal *** processes regulate abiotic stress responses,yet the molecular regulatory mechanisms in sweet potato remain *** this study,a NAC(NAM,ATAF1/2,and CUC2)transcription factor,IbNAC087,was identified,which is commonly upregulated in salt-and drought-tolerant *** of IbNAC087 increased salt and drought tolerance by increasing jasmonic acid(JA)accumulation and activating reactive oxygen species(ROS)scavenging,whereas silencing this gene resulted in opposite ***-rich IbNAC087-OE(overexpression)plants exhibited more stomatal closure than wild-type(WT)and IbNAC087-Ri plants under NaCl,polyethylene glycol,and methyl jasmonate ***087 functions as a nuclear transcriptional activator and directly activates the expression of the key JA biosynthesisrelated genes lipoxygenase(IbLOX)and allene oxide synthase(IbAOS).Moreover,IbNAC087 physically interacted with a RING-type E3 ubiquitin ligase NAC087-INTERACTING E3 LIGASE(IbNIEL),negatively regulating salt and drought tolerance in sweet *** ubiquitinated IbNAC087 to promote 26S proteasome degradation,which weakened its activation on IbLOX and *** findings provide insights into the mechanism underlying the IbNIEL-IbNAC087 module regulation of JA-dependent salt and drought response in sweet potato and provide candidate genes for improving abiotic stress tolerance in crops.

关键词： abiotic tolerance IbNAC087 IbNIEL JA sweet potato