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国家空间重构与中原经济区的形成 被引量:3
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作者 庞玉萍 王磊 《郑州航空工业管理学院学报》 2014年第4期15-19,共5页
在全球化信息化背景下,许多国家都在进行国家空间重构(state space reconstruction)。文章在简要回顾国外空间重构理论的基础上,对我国的空间重构的特点进行了分析,指出我国空间重构与国外有相通之处,也有不同之处。无论西方还是我国都... 在全球化信息化背景下,许多国家都在进行国家空间重构(state space reconstruction)。文章在简要回顾国外空间重构理论的基础上,对我国的空间重构的特点进行了分析,指出我国空间重构与国外有相通之处,也有不同之处。无论西方还是我国都把"空间"作为生产要素在进行调整和运用,空间重构的过程表现为各类地域组织(如城市,国家)的尺度重组(rescaling);但所不同的是,我国还受国家区域发展战略的调控。文章选取中原经济区的形成过程(process)作为案例实证。 展开更多
关键词 国家空间 尺度 区域发展战略 中原经济区
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论国家二重属性与政府的经济职能——兼论政府和市场的关系 被引量:18
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作者 刘凤义 张朝鹏 《社会科学战线》 CSSCI 北大核心 2017年第10期36-42,共7页
国家具有二重属性,即阶级属性和公共属性,二者是辩证统一的关系,阶级属性处于支配地位,公共属性处于从属地位,统一于统治阶级的利益。国家的二重属性决定政府经济职能的不同层次:国家的阶级属性决定政府的特殊经济职能,从根本上维护统... 国家具有二重属性,即阶级属性和公共属性,二者是辩证统一的关系,阶级属性处于支配地位,公共属性处于从属地位,统一于统治阶级的利益。国家的二重属性决定政府经济职能的不同层次:国家的阶级属性决定政府的特殊经济职能,从根本上维护统治阶级的利益;国家的公共属性决定政府的基本经济职能,如调控经济运行、调节经济结构、避免严重的贫富分化、保持经济稳定增长和维护市场经济秩序等。政府和市场的关系本质上是国家和市场的关系。我国社会主义国家性质决定了政府的特殊经济职能:不断扩大再生产社会主义新型生产关系;坚持市场经济中的共享发展和共同富裕方向;通过做强做优做大国有企业更好地驾驭市场经济。 展开更多
关键词 国家属性 政府的特殊经济职能 政府的基本经济职能 政府和市场关系 社会主义生产关系
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基于AUV垂直面运动控制的状态增减多模型切换 被引量:2
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作者 周焕银 李一平 +1 位作者 刘开周 封锡盛 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2017年第8期1309-1315,共7页
自主水下机器人(autonomous underwater vehicle,AUV)系统垂直面运动具有强耦合性、非线性等特点导致AUV系统垂直面难以精确控制,且其纵倾角需控制在某一阈值内,以保证系统安全。根据以上控制要求与AUV垂直面运动模型特点,提出将其解耦... 自主水下机器人(autonomous underwater vehicle,AUV)系统垂直面运动具有强耦合性、非线性等特点导致AUV系统垂直面难以精确控制,且其纵倾角需控制在某一阈值内,以保证系统安全。根据以上控制要求与AUV垂直面运动模型特点,提出将其解耦为深度控制子模型与纵倾角控制子模型,构建AUV系统垂直面运动控制模型集,根据模型集所含两子模型特点,提出了状态变量增减的多模型切换的概念。基于切换系统稳定判据——共同Lyapunov函数法,提出了变加权多模型切换策略,实现了切换过程的稳定性,避免了切换过程的抖动问题。多次湖泊试验证明,加权多模型切换策略避免了由于期望深度变化而造成的执行机构饱和、深度和纵倾角超调量过大等问题,且改善了AUV系统深度运动的静动态控制品质。 展开更多
关键词 自主水下机器人 加权多模型切换控制 共同LYAPUNOV函数 垂直面控制模型 纵倾角控制模型 切换系统
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丙烯酸-2,4,6-三硝基苯乙酯的合成及热分解 被引量:2
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作者 刘强强 金波 +3 位作者 彭汝芳 舒远杰 楚士晋 董海山 《含能材料》 EI CAS CSCD 北大核心 2012年第5期579-582,共4页
以TNT、甲醛为原料,在弱碱性条件下反应合成得到2,4,6-三硝基苯乙醇(PicCH2CH2OH);PicCH2CH2OH在浓硫酸催化下和丙烯酸在甲苯中回流反应24h,合成得到丙烯酸-2,4,6-三硝基苯乙酯,产率为62%。采用紫外可见光谱(UV-Vis)、核磁共振氢谱(1HN... 以TNT、甲醛为原料,在弱碱性条件下反应合成得到2,4,6-三硝基苯乙醇(PicCH2CH2OH);PicCH2CH2OH在浓硫酸催化下和丙烯酸在甲苯中回流反应24h,合成得到丙烯酸-2,4,6-三硝基苯乙酯,产率为62%。采用紫外可见光谱(UV-Vis)、核磁共振氢谱(1HNMR)、红外光谱(FTIR)、质谱(MS)以及元素分析等对产物结构进行了表征。利用热重分析(TG)对产物热稳定性进行了研究,采用Kissinger方法和Ozawa方法计算其热分解活化能Ea分别为99.78,102.96kJ·mol-1。 展开更多
关键词 有机化学 2 4 6-三硝基苯乙醇 丙烯酸-2 4 6-三硝基苯乙酯 热稳定性 活化能
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胶州湾北部软底大型底栖动物丰度和生物量的研究 被引量:17
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作者 于子山 张志南 王诗红 《中国海洋大学学报(自然科学版)》 CAS CSCD 2000年第z1期-,共7页
1995年3~11月对胶州湾北部软底海域进行了 两月一次的大型底栖动物调查。调查期间,大型底栖动物总平均丰度和总平均生物量分别为 1891.3 inds./m2和41.9 g.w.w/m2。与该海域有关大型底栖动物丰度和生物量的历史 资料相比较,本研究所... 1995年3~11月对胶州湾北部软底海域进行了 两月一次的大型底栖动物调查。调查期间,大型底栖动物总平均丰度和总平均生物量分别为 1891.3 inds./m2和41.9 g.w.w/m2。与该海域有关大型底栖动物丰度和生物量的历史 资料相比较,本研究所得到的大型底栖动物丰度值显著增加,生物量值则有较明显的下降, 初步分析了发生这些变化主要原因。丰度和生物量比较曲线表明,所研究海域底栖生物群落 处于中等干扰(即污染的影响 )状态。 展开更多
关键词 胶州湾 大型底栖动物 丰度 生物量
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钻井液设计专家系统规则库的检测算法 被引量:3
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作者 李建 习文风 《计算机工程与应用》 CSCD 北大核心 2020年第4期256-261,共6页
钻井液设计专家系统规则库的规模随着规则的更新与日俱增,对规则库的维护工作变得日益重要。针对规则库的从属、冗余、环路和冲突等问题提出一种检测算法。引入有向超图来表示规则库中的规则;用邻接矩阵表示该有向超图,并计算出它的可... 钻井液设计专家系统规则库的规模随着规则的更新与日俱增,对规则库的维护工作变得日益重要。针对规则库的从属、冗余、环路和冲突等问题提出一种检测算法。引入有向超图来表示规则库中的规则;用邻接矩阵表示该有向超图,并计算出它的可达矩阵和总可达矩阵;用总可达矩阵对规则库进行检测,找出规则库中存在的问题。实验表明,与已有的检测算法相比,该算法能够有效地检测出规则库中存在的问题,同时构建的邻接矩阵规模较小,在保证算法简洁的基础上提高了效率。 展开更多
关键词 专家系统 规则库 有向超图 邻接矩阵 可达矩阵 总可达矩阵
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国家空间重构视角下的北京通州转型升级
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作者 邹晖 罗小龙 陆建城 《北京规划建设》 2020年第1期71-74,共4页
本文对改革开放以来通州的发展历程进行了总体回顾,研究引入了国家空间选择理论,建立通州的转型升级与国家空间选择重构的宏观过程之间的联系,从国家空间治理的角度分析通州转型升级的内在规律,以加深对通州发展路径的认识。研究表明:首... 本文对改革开放以来通州的发展历程进行了总体回顾,研究引入了国家空间选择理论,建立通州的转型升级与国家空间选择重构的宏观过程之间的联系,从国家空间治理的角度分析通州转型升级的内在规律,以加深对通州发展路径的认识。研究表明:首先,北京城市副中心的产生是受国家空间治理尺度区域化重构影响的结果;其次,通州从卫星城到副中心的转型升级历程体现了国家空间选择重构的路径依赖和分层叠加特性;再次,国家空间选择影响了北京城市空间重构过程,使通州的定位从卫星城逐渐转型升级为城市副中心。 展开更多
关键词 国家空间 通州 城市副中心 转型升级
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欧元区重债国家的结构改革析论
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作者 陈新 《欧洲研究》 CSSCI 北大核心 2015年第2期42-59,6,共18页
在欧债危机背景下,欧元区重债国家结构改革的必要性和迫切性日益凸显。这些国家的结构改革虽有其特性,但也有共性,主要体现在公共管理、税制、产品市场和劳动力市场等领域。接受救助的重债国因受到硬约束的压力,改革力度大,因而取得了... 在欧债危机背景下,欧元区重债国家结构改革的必要性和迫切性日益凸显。这些国家的结构改革虽有其特性,但也有共性,主要体现在公共管理、税制、产品市场和劳动力市场等领域。接受救助的重债国因受到硬约束的压力,改革力度大,因而取得了初步效果。没有接受救助的重债国的改革则呈现软约束状态,其经济增长也受到影响。总体而言,欧洲的结构改革是一项未竟的事业,还需要持续努力并保持改革的动力。 展开更多
关键词 欧元区 国家 结构改革 劳动力市场改革 产品市场改革
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Intercalation Assembly Method and Intercalation Process Control of Layered Intercalated Functional Materials 被引量:5
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作者 李凯涛 王桂荣 +2 位作者 李殿卿 林彦军 段雪 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期453-462,共10页
Layered intercalated functional materials of layered double hydroxide type are an important class of functional materials developed in recent years. Based on long term studies on these materials in the State Key Labor... Layered intercalated functional materials of layered double hydroxide type are an important class of functional materials developed in recent years. Based on long term studies on these materials in the State Key Laboratory of Chemical Resource Engineering in Beiiing University of Chemical Technology, the orinciole for the design of controlled intercalation processes in the light of tuture production processing requirements has been developed. Intercalation assembly methods and technologies have been invented to control the intercalation process for preparing layered intercalated materials with various structures and functions. 展开更多
关键词 layered intercalated structure functional material intercalation assembly methods intercalation process
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East China Summer Rainfall during ENSO Decaying Years Simulated by a Regional Climate Model 被引量:4
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作者 ZENG Xian-Feng LI Bo +2 位作者 FENG Lei LIU Xiao-Juan ZHOU Tian-Jun 《Atmospheric and Oceanic Science Letters》 2011年第2期91-97,共7页
The performance of the Climate version of the Regional Eta-coordinate Model (CREM), a regional climate model developed by State Key Laboratory of Numerical modeling for Atmospheric Science and Geophysical Fluid Dyna... The performance of the Climate version of the Regional Eta-coordinate Model (CREM), a regional climate model developed by State Key Laboratory of Numerical modeling for Atmospheric Science and Geophysical Fluid Dynamics/Institute of Atmospheric Physics (LASG/IAP), in simulating rainfall anomalies during the ENSO decaying summers from 1982 to 2002 was evalu- ated. The added value of rainfall simulation relative to reanalysis data and the sources of model bias were studied. Results showed that the model simulated rainfall anomalies moderately well. The model did well at capturing the above-normal rainfall along the Yangtze River valley (YRV) during E1 Nifio decaying summers and the below and above-normal rainfall centers along the YRV and the Huaihe River valley (HRV), respectively, during La Nifia decaying summers. These features were not evident in rainfall products derived from the reanalysis, indicating that rainfall simulation did add value. The main limitations of the model were that the simulated rainfall anomalies along the YRV were far stronger and weaker in magnitude than the observations during E1 Nifio decaying summers and La Nifia decaying summers, respectively. The stronger magnitude above-normal rainfall during E1 Nifio decaying summers was due to a stronger northward transport of water vapor in the lower troposphere, mostly from moisture advection. An artificial, above-normal rainfall center was seen in the region north to 35°N, which was associated with stronger northward water vapor transport. Both lower tropospheric circulation bias and a wetter model atmosphere contributed to the bias caused by water vapor transport. There was a stronger southward water vapor transport from the southern boundary of the model during La Nifia decaying summers; less remaining water vapor caused anomalously weaker rainfall in the model as compared to observations. 展开更多
关键词 East China rainfall ENSO decaying summers regional climate model water vapor
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The spring prediction barrier in ENSO hindcast experiments using the FGOALS-g model 被引量:2
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作者 严厉 俞永强 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第6期1093-1104,共12页
The Flexible Global Ocean-Atmosphere-Land System Model-gamil (FGOALS-g) was used to study the spring prediction barrier (SPB) in an ensemble system. This coupled model was developed and maintained at the State Key Lab... The Flexible Global Ocean-Atmosphere-Land System Model-gamil (FGOALS-g) was used to study the spring prediction barrier (SPB) in an ensemble system. This coupled model was developed and maintained at the State Key Laboratory of Atmospheric Sciences and Geophysical Fluid Dynamics (LASG). There are two steps in our hindcast experiments. The first is to integrate the coupled model continuously with sea surface temperature (SST) nudging, from 1971 to 2006. The second is to carry out a series of one-year hindcasts without SST nudging, by adopting initial values from the first step on January 1 st , April 1st , July 1st , and October 1st , from 1982 to 2005. We generate 10 ensemble members for a particular start date (1st ) by choosing different atmospheric and land conditions around the hindcast start date (1st through 10th ). To estimate the predicted SST, two methods are used: (1) Anomaly Correlation Coefficient and its rate of decrease; and (2) Talagrand distribution and its standard deviation. Results show that FGOALS-g offers a reliable ensemble system with realistic initial atmospheric and oceanic conditions, and high anomaly correlation (>0.5) within 6 month lead time. Further, the ensemble approach is effective, in that the anomaly correlation of ensemble mean is much higher than that of most individual ensemble members. The SPB exists in the FGOALS-g ensemble system, as shown by anomaly correlation and equal likelihood. Nevertheless, the role of the ensemble mean in reducing the SPB of ENSO prediction is significant. The rate of decrease of the ensemble mean is smaller than the largest deviations by 0.04-0.14. At the same time, the ensemble system "equal likelihood" declines during spring. An ensemble mean helps give a correct prediction direction, departing from largely-deviated ensemble members. 展开更多
关键词 spring prediction barrier ensemble ENSO hindcast experiments equal likelihood
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广西壮族自治区人民政府关于自治区主席副主席工作分工的通知
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《广西壮族自治区人民政府公报》 2014年第17期26-27,共2页
桂政发[2014]36号各市、县人民政府,自治区农垦局,自治区人民政府各组成部门、各直属机构:自治区人民政府实行主席负责制,副主席协助主席工作。现将自治区主席、副主席工作分工通知如下:陈武主席领导自治区人民政府全面工作,负责机构编... 桂政发[2014]36号各市、县人民政府,自治区农垦局,自治区人民政府各组成部门、各直属机构:自治区人民政府实行主席负责制,副主席协助主席工作。现将自治区主席、副主席工作分工通知如下:陈武主席领导自治区人民政府全面工作,负责机构编制、监察、财政、审计工作。主管自治区国防动员委员会、编委、监察厅、财政厅、审计厅。黄道伟副主席负责自治区人民政府常务工作,协助负责机构编制、财政、审计工作。 展开更多
关键词 副主席 机构编制 自治区工业 国防动员 农垦局 工作分工 人力资源 直属机构 凭祥综合保税区 国家重
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Contribution to the Investigation of Structure and Origin of the East African Graben by Gravi metry
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作者 Tondozi Keto LIU Tianyou 《Geo-Spatial Information Science》 2005年第4期291-296,共6页
For our investigation we have 235 measurements done in the east part of Democratic Republic of Congo by P.Herrinck during a magnetic survey including the graben region from the parallel joining Goma city and Mahagi ci... For our investigation we have 235 measurements done in the east part of Democratic Republic of Congo by P.Herrinck during a magnetic survey including the graben region from the parallel joining Goma city and Mahagi city, the region between Albert and Aka lakes, and the route from Aba to Kinsagani. During the surveys the density of recording points has been selected according to the importance of anomalies. In this way, the offset was 1 km where the disturbance was high in Goma city and 20 km have been sufficient along the route from Aba to Kinsagani. For the topographic and isostatic reductions only one cartographic document has been chosen that was the international map of the scale 1/1 000 000 which presents a certain characteristic of homogeneity. 展开更多
关键词 gravity anomaly data reductions compensation OFFSET ISOSTASY
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催化裂解多产丙烯获得突破
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《中国石油和化工》 2007年第23期61-62,共2页
我国催化裂解多产丙烯技术取得重大成果。中国石油大学(华东)重质油国家重点实验室自主研发的两段提升管催化裂解多产丙烯(TMP)技术的工业化试验表明:常压渣油经催化裂解,丙烯收率超过18%,液化气、汽油和柴油收率之和接近83%... 我国催化裂解多产丙烯技术取得重大成果。中国石油大学(华东)重质油国家重点实验室自主研发的两段提升管催化裂解多产丙烯(TMP)技术的工业化试验表明:常压渣油经催化裂解,丙烯收率超过18%,液化气、汽油和柴油收率之和接近83%。该成果将使炼油化工一体化技术发展向前迈出重要一步,并将对我国乃至世界丙烯生产带来重要影响。 展开更多
关键词 催化裂解 丙烯 中国石油大学(华东)质油国家重点实验室 自主研发 两段提升管
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Research on multiple elimination methods in inverse data space based on randomized singular value decomposition 被引量:1
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作者 WANG Tiexing WANG Deli +2 位作者 HU Bin SUN Jing SU Xiaobo 《Global Geology》 2017年第1期59-63,共5页
Based on surfaced-related multiple elimination (SRME) , this research has derived the methods on multiples elimination in the inverse data space. Inverse data processing means moving seismic data from forwar... Based on surfaced-related multiple elimination (SRME) , this research has derived the methods on multiples elimination in the inverse data space. Inverse data processing means moving seismic data from forward data space (FDS) to inverse data space ( IDS) . The surface-related multiples and primaries can then be sepa-rated in the IDS, since surface-related multiples wi l l form a focus region in the IDS. Muting the multiples ener-gy can achieve the purpose of multiples elimination and avoid the damage to primaries energy during the process of adaptive subtraction. Randomized singular value decomposition ( RSYD) is used to enhance calculation speed and improve the accuracy in the conversion of FDS to IDS. The synthetic shot record of the salt dome model shows that the relationship between primaries and multiples is simple and clear, and RSVD can easily eliminate multiples and save primaries energy. Compared with conventional multiples elimination methods and ordinary methods of multiples elimination in the inverse data space, this technique has an advantage of high cal-culation speed and reliable outcomes. 展开更多
关键词 multiple elimination SRME inverse data space feedback model RSYD
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Remaining Architectural Heritage in Kosovo, Their Durability and Sustainability
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作者 Shqipe Nixha Violeta Nushi 《Journal of Literature and Art Studies》 2012年第6期651-663,共13页
This paper work aims to response the request for immediate intervention of cultural heritage preservation in Kosovo, with the aim of protection against the harmful consequences of insufficient knowledge leading to a m... This paper work aims to response the request for immediate intervention of cultural heritage preservation in Kosovo, with the aim of protection against the harmful consequences of insufficient knowledge leading to a misuse of technology and to ill-considered approaches. The DGT (dwelling-garret type) is an important vernacular study case. The DGT is a historic building of 18th century, located in the core of Lebusha Village, Municipality of Peja, an architectural construction characterized by two concentric volumes at rectangular layout, very dynamic at horizontal composition, obtained by the movement of two differently constructional materials volumes, stone masonry and timber assembly, and covered with roof clay tiles. In view of its esthetic and artistic values, its important role at developing chain of Kosovo's rural dwellings typology, and its method of construction, the building should be listed as a monument under state protection. Hence, immediate protection interventions, such as conservation of wooden and stone envelope, improvement of walls and finish works, and drainage infrastructure, are considered as the minimum requirement. 展开更多
关键词 architectural heritage DGT (dwelling-garret type) DURABILITY SUSTAINABILITY
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Smoothing GNSS Time Series with Asymmetric Simple Moving Averages
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作者 Jose Nuno Lima Joao Casaca 《Journal of Civil Engineering and Architecture》 2012年第6期745-750,共6页
There is an increasing trend to apply GNSS continuous observation of short baselines to the monitoring of engineering works, such as bridges and dams, for their structural analysis and safety control. In the case of l... There is an increasing trend to apply GNSS continuous observation of short baselines to the monitoring of engineering works, such as bridges and dams, for their structural analysis and safety control. In the case of large dams, one important application of the GNSS continuous observation is thc establishment of early warning systems that demand accurate, frequently updated information and where the analysis of the baseline time series, in order to separate signal from noise is mandatory. The paper presents a study on the performance of linear filters of the asymmetric moving average type to smooth baseline time series. The transfer function of the filter is adopted as a smoothing criterion to choose an adequate order for the moving average, in face of the spectral density function of the baseline time series. Onc series of measurements of a short test baseline (325 m), materialized in the campus of the National Laboratory for Civil Engineering, is used as an example of the proposed strategy. 展开更多
关键词 GNSS moving averages spectral density.
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New Method for Synthesis of Formamide from CO_2
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《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第4期80-80,共1页
The research team headed by Ding Kuiling working in the State Key Laboratory of Metallorganic Chemistry at the CAS Shanghai Institute of Organic Chemistry by using the princer type ruthenium complex catalyst has succe... The research team headed by Ding Kuiling working in the State Key Laboratory of Metallorganic Chemistry at the CAS Shanghai Institute of Organic Chemistry by using the princer type ruthenium complex catalyst has successfully developed a new method for effectively synthesizing formamide compounds from CO_2,H2 and primary or secondary amines serving as the feedstocks. 展开更多
关键词 formamide synthesizing headed serving methanol amines basically hydrogenation carbonate stepwise
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别样的春节
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作者 庄妍 《世纪之星—初中版》 2021年第3期139-140,共2页
在中国人的眼里,年是最大的节日,它不仅是家人的团聚,更是亲情、爱情、友情的交汇。有多少人在分离的时候,会说,我们过年的时候聚吧!过年,就是在一起。这也是我们中华民族传统佳节。然而,因为疫情,回家过年不再是我们提倡的,更多的人,... 在中国人的眼里,年是最大的节日,它不仅是家人的团聚,更是亲情、爱情、友情的交汇。有多少人在分离的时候,会说,我们过年的时候聚吧!过年,就是在一起。这也是我们中华民族传统佳节。然而,因为疫情,回家过年不再是我们提倡的,更多的人,响应国家号召,选择就地过年。舍小家,为大家。这是一种精神,它比大年三十的烟花更灿烂,更闪耀。 展开更多
关键词 留守 国家
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Tree Rings Tell Moisture Variability on Tibetan Plateau
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《Bulletin of the Chinese Academy of Sciences》 2015年第4期238-238,共1页
Tibetan Plateau(TP)is known as"Asia’s Water Tower",but it remains an interesting question whether the water supply to the north of the plateau is the same with that to the south.Dr.ZHANG Qibin and coworkers from ... Tibetan Plateau(TP)is known as"Asia’s Water Tower",but it remains an interesting question whether the water supply to the north of the plateau is the same with that to the south.Dr.ZHANG Qibin and coworkers from the State Key Laboratory of Vegetation and Environmental Change.CAS Institute of Botany recently tried to answer it from their studies of tree rings.They found evidences for different moisture conditions on the north and south of the plateau during the past five and a half centuries,and particularly, 展开更多
关键词 Plateau Tibetan north plateau moisture answer rings latitude scenario records
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