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Assessment of land degradation in Inner Mongolia between 2000 and 2020 based on remote sensing data 被引量:1
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作者 Linlin Zhao Kun Jia +2 位作者 Xin Liu Jie Li Mu Xia 《Geography and Sustainability》 CSCD 2023年第2期100-111,共12页
Achieving land degradation neutrality(LDN)worldwide is a significant target of the Sustainable Development Goal(SDG15.3).Inner Mongolia,as a typical dryland region in northern China,has carried out several large-scale... Achieving land degradation neutrality(LDN)worldwide is a significant target of the Sustainable Development Goal(SDG15.3).Inner Mongolia,as a typical dryland region in northern China,has carried out several large-scale ecological restoration programs to combat land degradation.However,there is a lack of comprehensive assess-ment of its land degradation situation after ecological programs implementation,which is of great significance to supporting SDG15.3 in China.This study analyzed the land degradation situation using the improved SDG15.3.1 calculation framework based on fine resolution data in Inner Mongolia from 2000 to 2020,and finally compre-hensively evaluated the land status of the whole region and those subject to ecological programs.The results show that net land restoration proportion of various ecological project regions and whole region continues to increase.The scope of the Grain for Green Program(GGP)had the largest proportion of net land restoration while the Natural Reserve Program(NRP)had the lowest proportion from 2000 to 2020.The net land restoration area of Inner Mongolia during 2000-2010 and 2010-2020 was 35,800 km 2 and 65,300 km 2,respectively.Overall,Inner Mongolia has achieved statistically zero growth in land degradation under the governance of ecological restora-tion programs.Therefore,reasonable planning,well monitoring,and timely assessment of ecological restoration programs are crucial to support SDG15.3. 展开更多
关键词 SDG15.3 Land degradation neutrality(LDN) Land degradation Ecological programs inner Mongolia
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Enhanced soil moisture improves vegetation growth in an arid grassland of Inner Mongolia Autonomous Region, China
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作者 ZHANG Hui Giri R KATTEL +3 位作者 WANG Guojie CHUAI Xiaowei ZHANG Yuyang MIAO Lijuan 《Journal of Arid Land》 SCIE CSCD 2023年第7期871-885,共15页
Climate change impacts on grasslands that cover a quarter of the global land area, have become unprecedented during the 21~(st) century. One of the important ecological realms, arid grasslands of northern China, which... Climate change impacts on grasslands that cover a quarter of the global land area, have become unprecedented during the 21~(st) century. One of the important ecological realms, arid grasslands of northern China, which occupy more than 70% of the region's land area. However, the impact of climate change on vegetation growth in these arid grasslands is not consistent and lacks corresponding quantitative research. In this study, NDVI(normalized difference vegetation index) and climate factors including temperature, precipitation, solar radiation, soil moisture, and meteorological drought were analyzed to explore the determinants of changes in grassland greenness in Inner Mongolia Autonomous Region(northern China) during 1982–2016. The results showed that grasslands in Inner Mongolia witnessed an obvious trend of seasonal greening during the study period. Two prominent climatic factors,precipitation and soil moisture accounted for approximately 33% and 27% of grassland NDVI trends in the region based on multiple linear regression and boosted regression tree methods. This finding highlights the impact of water constraints to vegetation growth in Inner Mongolia's grasslands. The dominant role of precipitation in regulating grassland NDVI trends in Inner Mongolia significantly weakened from 1982 to 1996, and the role of soil moisture strengthened after 1996. Our findings emphasize the enhanced importance of soil moisture in driving vegetation growth in arid grasslands of Inner Mongolia, which should be thoroughly investigated in the future. 展开更多
关键词 grassland growth normalized difference vegetation index climate change soil moisture inner Mongolia
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Modeling the energetic electron fluxes in the inner radiation belt based on a drift-source model
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作者 Zheng Xiang BinBin Ni +8 位作者 YangXiZi Liu XuDong Gu Song Fu Wei Xu Xing Cao Xin Ma DeYu Guo JunHu Dong JingLe Hu 《Earth and Planetary Physics》 EI CSCD 2023年第1期100-108,共9页
The Macao Science Satellite-1(MSS-1),designed by the Macao University of Science and Technology and the National Space Science Center(NSSC)of China,is equipped to detect the fine structure of the magnetic field over t... The Macao Science Satellite-1(MSS-1),designed by the Macao University of Science and Technology and the National Space Science Center(NSSC)of China,is equipped to detect the fine structure of the magnetic field over the South Atlantic Anomaly(SAA)region,monitoring geomagnetic field variations,and obtaining the energetic electron spectrum distributions in the Earth’s inner radiation belt.In this study,we simulate the distributions of trapped,quasi-trapped,and untrapped electrons along the orbit of MSS-1 based on a drift-source model.The simulation results show that the particle detector with 90°looking direction can observe trapped electrons in the SAA region,untrapped electrons in the regions conjugated with the SAA region at the north hemisphere,and quasitrapped electrons in all other regions.In contrast,the detectors with<60°looking directions can measure only untrapped electrons.Generally,quasi-trapped electron fluxes accumulate along the drift trajectory and are due primarily to CRAND,until reaching the SAA region where quasi-trapped electrons are all lost into the atmosphere. 展开更多
关键词 Earth’s inner belt drift-source model quasi-trapped electron CRAND
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Responses of vegetation yield to precipitation and reference evapotranspiration in a desert steppe in Inner Mongolia,China
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作者 LI Hongfang WANG Jian +2 位作者 LIU Hu MIAO Henglu LIU Jianfeng 《Journal of Arid Land》 SCIE CSCD 2023年第4期477-490,共14页
Drought,which restricts the sustainable development of agriculture,ecological health,and social economy,is affected by a variety of factors.It is widely accepted that a single variable cannot fully reflect the charact... Drought,which restricts the sustainable development of agriculture,ecological health,and social economy,is affected by a variety of factors.It is widely accepted that a single variable cannot fully reflect the characteristics of drought events.Studying precipitation,reference evapotranspiration(ET_(0)),and vegetation yield can derive information to help conserve water resources in grassland ecosystems in arid and semi-arid regions.In this study,the interactions of precipitation,ET_(0),and vegetation yield in Darhan Muminggan Joint Banner(DMJB),a desert steppe in Inner Mongolia Autonomous Region,China were explored using two-dimensional(2D)and three-dimensional(3D)joint distribution models.Three types of Copula functions were applied to quantitatively analyze the joint distribution probability of different combinations of precipitation,ET_(0),and vegetation yield.For the precipitation–ET_(0)dry–wet type,the 2D joint distribution probability with precipitation≤245.69 mm/a or ET_(0)≥959.20 mm/a in DMJB was approximately 0.60,while the joint distribution probability with precipitation≤245.69 mm/a and ET_(0)≥959.20 mm/a was approximately 0.20.Correspondingly,the joint return period that at least one of the two events(precipitation was dry or ET_(0)was wet)occurred was 2 a,and the co-occurrence return period that both events(precipitation was dry and ET_(0)was wet)occurred was 5 a.Under this condition,the interval between dry and wet events would be short,the water supply and demand were unbalanced,and the water demand of vegetation would not be met.In addition,when precipitation remained stable and ET_(0)increased,the 3D joint distribution probability that vegetation yield would decrease due to water shortage in the precipitation–ET_(0)dry–wet years could reach up to 0.60–0.70.In future work,irrigation activities and water allocation criteria need to be implemented to increase vegetation yield and the safety of water resources in the desert steppe of Inner Mongolia. 展开更多
关键词 PRECIPITATION reference evapotranspiration vegetation yield Copula functions desert steppe dry and wet events inner Mongolia
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Spatial changes and driving factors of lake water quality in Inner Mongolia, China
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作者 REN Xiaohui YU Ruihong +10 位作者 LIU Xinyu SUN Heyang GENG Yue QI Zhen ZHANG Zhuangzhuang LI Xiangwei WANG Jun ZHU Penghang GUO Zhiwei WANG Lixin XU Jifei 《Journal of Arid Land》 SCIE CSCD 2023年第2期164-179,共16页
Lakes play important roles in sustaining the ecosystem and economic development in Inner Mongolia Autonomous Region of China,but the spatial patterns and driving mechanisms of water quality in lakes so far remain uncl... Lakes play important roles in sustaining the ecosystem and economic development in Inner Mongolia Autonomous Region of China,but the spatial patterns and driving mechanisms of water quality in lakes so far remain unclear.This study aimed to identify the spatial changes in water quality and the driving factors of seven lakes(Juyanhai Lake,Ulansuhai Lake,Hongjiannao Lake,Daihai Lake,Chagannaoer Lake,Hulun Lake,and Wulannuoer Lake)across the longitudinal axis(from the west to the east)of Inner Mongolia.Large-scale research was conducted using the comprehensive trophic level index(TLI(Σ)),multivariate statistics,and spatial analysis methods.The results showed that most lakes in Inner Mongolia were weakly alkaline.Total dissolved solids and salinity of lake water showed obvious zonation characteristics.Nitrogen and phosphorus were identified as the main pollutants in lakes,with high average concentrations of total nitrogen and total phosphorus being of 4.05 and 0.21 mg/L,respectively.The values of TLI(Σ)ranged from 49.14 to 71.77,indicating varying degrees of lake eutrophication,and phosphorus was the main driver of lake eutrophication.The lakes of Inner Mongolia could be categorized into lakes to the west of Daihai Lake and lakes to the east of Daihai Lake in terms of salinity and TLI(Σ).The salinity levels of lakes to the west of Daihai Lake exceeded those of lakes to the east of Daihai Lake,whereas the opposite trend was observed for lake trophic level.The intensity and mode of anthropogenic activities were the driving factors of the spatial patterns of lake water quality.It is recommended to control the impact of anthropogenic activities on the water quality of lakes in Inner Mongolia to improve lake ecological environment.These findings provide a more thorough understanding of the driving mechanism of the spatial patterns of water quality in lakes of Inner Mongolia,which can be used to develop strategies for lake ecosystem protection and water resources management in this region. 展开更多
关键词 SALINITY lake eutrophication lake water quality comprehensive trophic level index anthropogenic activities Daihai Lake inner Mongolia
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The Inner Structure of the Intrinsic Electron and the Origin of Self-Mass
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作者 Victor Vaguine 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期174-189,共16页
A brief review and analysis of two historical models of the electron, the charged spinning sphere and Goudsmit and Uhlenbeck’s concept, is presented. It is shown that the enormous potential of classical electrodynami... A brief review and analysis of two historical models of the electron, the charged spinning sphere and Goudsmit and Uhlenbeck’s concept, is presented. It is shown that the enormous potential of classical electrodynamics has been underutilized in particle physics. Such observation leads to discovery of a principal component in the electron inner structure—the charged c-ring. The intrinsic (fundamental) electron model based on the charged c-ring successfully explains the ontology of the charge fractionation in quantum chromodynamics and the formation of Cooper pairs in superconductivity. The c-ring properties are explained on the basis of the General Compton Conditions as defined. Properties of the charged c-ring include the explanation of the boundary conditions, electro-magnetostatic field configuration, self-mass, spin, magnetic moment, and the gyromagnetic ratio. The self-mass of the intrinsic electron is 100% electro-magnetostatic and it is shown how to compute its value. The classical-quantum divide no longer exists. Relation between the intrinsic electron and the electron is fundamentally defined. The electron is the composite fermion consisting of the intrinsic electron and the neutrino. The ontology of the anomaly in the electron magnetic moment is demonstrated—it is due to the addition of the neutrino magnetic moment to the overall electron magnetic moment. The intrinsic electron replaces the W? boson in particle physics, resulting in a fundamental implication for the Standard Model. 展开更多
关键词 Intrinsic Electron inner Structure Electro-Magnetostatic Self-Mass General Compton Conditions Charged C-Ring Visualization C-Ring Length Constant
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The Intrinsic Electron with Its Properties Such as Inner Structure and Self-Mass Is in Conflict with Quantum Field Theory
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作者 Victor Vaguine 《Journal of High Energy Physics, Gravitation and Cosmology》 2023年第3期583-595,共13页
The quantum field theory (QFT) is one of branches of the Standard Model. According to QFT, quantum fields are the primary entities and particles are the excitations of these fields, coming in discrete lumps with no in... The quantum field theory (QFT) is one of branches of the Standard Model. According to QFT, quantum fields are the primary entities and particles are the excitations of these fields, coming in discrete lumps with no inner structures and with properties assigned by declaration. Such view is in conflict with the observed vacuum energy density, 140 orders of magnitudes less than required by the QFT. In addition, such view is challenged by Aphysical Quantum Mechanics (AQM), a deeper quantum theory. According to AQM, the fundamental understanding of quantum reality is expanded by the addition of two fundamental categories, aphysical and elementary consciousness of elementary particles. Based on AQM and as an example, the total ontology of the intrinsic (fundamental) electron is presented with its inner structure of perfect geometry consisting of the physical charged c-ring and aphysical cylinder, and with its properties such as self-mass, spin, magneto-electrostatic field configuration and magnetic moment. The position parameter in the inner structure demonstrates that there are no two identical intrinsic electrons in the Universe thus placing a question mark over the QFT principle of indistinguishability. 展开更多
关键词 Quantum Reality Physical-Aphysical Intrinsic Electron Charged C-Ring Aphysical Cylinder Elementary Consciousness Position Parameter Constant U Ontology Self-Mass Indistinguishable inner Structure
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毫米波多内导体布喇格结构电磁特性研究
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作者 丁学用 王石峰 +1 位作者 王连胜 袁帅 《电波科学学报》 CSCD 北大核心 2024年第1期142-147,共6页
基于多模耦合理论,利用三维电磁仿真软件CST对毫米波双内导体和三内导体布喇格结构电磁特性分别进行了比较研究。结果表明:双内导体布喇格结构相比同轴布喇格结构可以抑制竞争模式,反射率稳定并接近1,对称性结构电磁特性优于非对称性结... 基于多模耦合理论,利用三维电磁仿真软件CST对毫米波双内导体和三内导体布喇格结构电磁特性分别进行了比较研究。结果表明:双内导体布喇格结构相比同轴布喇格结构可以抑制竞争模式,反射率稳定并接近1,对称性结构电磁特性优于非对称性结构;随着内导体距离同轴轴心距离的增大,双内导体布喇格结构频率响应带宽变宽,且当内导体距离同轴轴心距离较远时,带宽变宽趋势明显,而反射率值趋于稳定;对于三内导体布喇格结构,随着内导体距离同轴轴心距离的增大,频率响应带宽变窄,且当内导体距离同轴轴心距离较近时,带宽变宽趋势明显。因此,可根据实际需要恰当选择毫米波多内导体布喇格结构参数,拓宽其作为反射器或者滤波器的性能,提高模式的选择性及模式的纯度,改善布喇格结构的性能。 展开更多
关键词 同轴布喇格结构 双内导体结构 三内导体结构 频率响应 电场分布云图
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光致变色纱线在多层织物设计中的应用
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作者 牛建涛 刘雨晴 +2 位作者 黄紫娟 徐超武 蒋秀翔 《毛纺科技》 CAS 北大核心 2024年第1期15-18,共4页
为了丰富织物的多样性,利用光致变色纱线,结合表里换层双层组织,设计与开发了“P”字图案表里换层光致变色面料;并进一步设计与开发了上、中层表里换层结构的“E”字图案三层组织光致变色面料,实现了织物在光线照射下单面变色,而反面不... 为了丰富织物的多样性,利用光致变色纱线,结合表里换层双层组织,设计与开发了“P”字图案表里换层光致变色面料;并进一步设计与开发了上、中层表里换层结构的“E”字图案三层组织光致变色面料,实现了织物在光线照射下单面变色,而反面不显变色的特殊效果。将光致变色纱线与表里换层结构的双层或多层织物相结合,可以形成新型光致变色功能面料,为此类产品的开发与设计提供了一种新思路。 展开更多
关键词 光致变色 表里换层 多层织物 产品设计
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轴向移动内压力梁动力学的动网格法
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作者 郑伶俐 华洪良 +2 位作者 吴小锋 蔡宪逸 廖振强 《兵器装备工程学报》 CAS CSCD 北大核心 2024年第3期50-56,共7页
面向轴向移动内压力梁结构动力学特性研究,采用Lagrangian方法建立了轴向移动内压力梁的运动控制方程,基于有限元动网格法对轴向移动梁运动控制方程进行离散。将内压力作为边界条件,采用Newmark-β时间积分方法计算轴向移动梁动力学响应... 面向轴向移动内压力梁结构动力学特性研究,采用Lagrangian方法建立了轴向移动内压力梁的运动控制方程,基于有限元动网格法对轴向移动梁运动控制方程进行离散。将内压力作为边界条件,采用Newmark-β时间积分方法计算轴向移动梁动力学响应,并开展动力学特性研究。结果表明,建立的有限元动网格模型能够有效地实现轴向移动内压力梁动力学响应计算。轴向移动内压力梁在收缩运动过程中,自由端振动频率将逐渐增加。悬臂长度对梁自由端振动频率具有显著影响。同时,结构振动频率随内压力的增加而增加。本文中建立的有限元动网格模型能够为轴向移动内压力梁动力学研究提供新方法。 展开更多
关键词 轴向移动梁 动网格法 内压力 有限元法
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不同频率氮添加对内蒙古典型草原植物叶绿素的影响
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作者 王晓燕 陈俊刚 +1 位作者 张云海 毕华兴 《生态学报》 CAS CSCD 北大核心 2024年第11期4854-4864,共11页
大气氮沉降会影响植物功能性状的变异和进化,进而作用于植物个体和生态系统功能。研究草地生态系统植物功能性状在不同氮添加模式下的响应差异,对更准确地评估植物对环境变化的适应性至关重要。基于内蒙古草原野外长期氮沉降模拟实验平... 大气氮沉降会影响植物功能性状的变异和进化,进而作用于植物个体和生态系统功能。研究草地生态系统植物功能性状在不同氮添加模式下的响应差异,对更准确地评估植物对环境变化的适应性至关重要。基于内蒙古草原野外长期氮沉降模拟实验平台,研究氮添加频率对优势物种羊草和冰草叶绿素含量的影响,结果表明每年一次氮添加使羊草叶绿素含量增加最多(15.21%),而每月一次氮添加对冰草叶绿素含量影响最大(增加了14.74%)。氮添加尤其是每年一次氮添加显著增加了土壤铵态氮、硝态氮和无机氮含量,并使土壤pH显著降低。这些结果表明:羊草叶绿素含量对低频率氮添加响应更明显,而高频率氮添加对冰草叶绿素含量的影响更显著,这两类物种间养分吸收策略存在明显差异。启示低频率氮添加可能高估了氮沉降对羊草叶绿素含量的影响,而低估了对冰草叶绿素含量的影响,这对准确预测植物叶片功能性状对大气氮沉降的变异具有重要意义,并将有助于应用到植物功能性状预测生态系统功能和过程响应未来全球变化的模型中。 展开更多
关键词 氮添加 羊草 冰草 叶绿素含量 叶片性状 内蒙古
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基于磁传感器阵列的管道移位变形内检测
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作者 李健 刘天一 +2 位作者 王佳霖 刘珊 黄新敬 《电子测量与仪器学报》 CSCD 北大核心 2024年第2期76-84,共9页
海底管道的结构变形会增加管道断裂风险,从而造成极大的经济损失。本文提出一种基于球形内检测器和多通道磁传感器阵列的管道移位变形检测方法。根据磁机械效应,分析管道移位变形导致的管壁应力及管道内磁通密度变化规律。设计了检测器... 海底管道的结构变形会增加管道断裂风险,从而造成极大的经济损失。本文提出一种基于球形内检测器和多通道磁传感器阵列的管道移位变形检测方法。根据磁机械效应,分析管道移位变形导致的管壁应力及管道内磁通密度变化规律。设计了检测器结构布局及磁阵列采集方案,实现了管道内空间旋转磁通密度的高覆盖率采样。设计算法将旋转磁信号转换为管道坐标系下的平动磁信号,提取管道内等高线的磁数据,实现了多通道磁信息融合,提高了磁异常检出率。最后,开展了管道竖向加载和等效横向加载等移位变形的内检测试验。结果表明,管道在纵向受力变形状态下,管道内等高线上磁通密度纵向分量的离散度降低136.1μT;管道在等效横向受力变形状态下,管道内等高线上磁通密度横向分量的离散度降低123.1μT;球形内检测器所测得的磁通密度离散度能够反映出管道不同方向的移位变形,且管道变形越大,磁通密度离散度越小。 展开更多
关键词 管道弯曲 管道内磁通密度 磁阵列 球形内检测器
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名实难副——从《庄子》“内七篇”看庄子的语言游戏及解构策略
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作者 金洁 王玉明 《阜阳师范大学学报(社会科学版)》 2024年第2期23-28,共6页
解构作为一种古老的智慧并非德里达专有。天然解构大师庄子在《庄子》“内七篇”里以自由游戏的姿态切断了语言确定性的根基,并假借一群“名不副实”之人在“名”与“实”间进行自由游戏,从而揭露了“名”与“实”、能指与所指之间的矛... 解构作为一种古老的智慧并非德里达专有。天然解构大师庄子在《庄子》“内七篇”里以自由游戏的姿态切断了语言确定性的根基,并假借一群“名不副实”之人在“名”与“实”间进行自由游戏,从而揭露了“名”与“实”、能指与所指之间的矛盾和不一致。这一东方解构范例在传统庄子诠释学之外为我们提供了一个活泼且具有现代意义的庄子形象。同时,庄子对名言枷锁的解构,也使得儒道精神大放异彩,揭开了中国古代文化哲学儒道兼宗的序幕。 展开更多
关键词 庄子 “内七篇” 解构
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体外丝线牵拉辅助两孔腹腔镜内环缝合在治疗内环口皱褶冗厚斜疝中的应用
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作者 刘雪来 叶茂 +3 位作者 丁柏匀 管考平 张震 魏延栋 《中国微创外科杂志》 CSCD 北大核心 2024年第1期7-12,共6页
目的探讨体外丝线牵拉辅助两孔腹腔镜内环缝扎治疗内环皱褶冗厚斜疝的安全性、可行性。方法2019年10月~2023年2月,322例斜疝患儿接受两孔法腹腔镜内环缝扎,其中186例(292侧)内环皱褶冗厚患儿采用体外丝线牵拉法辅助。在腹腔镜监视下,针... 目的探讨体外丝线牵拉辅助两孔腹腔镜内环缝扎治疗内环皱褶冗厚斜疝的安全性、可行性。方法2019年10月~2023年2月,322例斜疝患儿接受两孔法腹腔镜内环缝扎,其中186例(292侧)内环皱褶冗厚患儿采用体外丝线牵拉法辅助。在腹腔镜监视下,针持持针经内环口外下缘入腹膜,于腹膜后间隙走行至精索血管外侧缘出针;于精索血管外侧缘进针,体外轻轻牵拉线尾,腹腔镜下见进针点附近后腹膜间隙增大,缝针顺势在后腹膜间隙跨越精索血管表面。相同方法牵拉和展开折叠在输精管-髂外血管间隙的腹膜皱褶,增大后腹膜间隙,缝针继续在后腹膜间隙贴近髂血管表面跨越Doom三角区冗厚的腹膜组织。相同方法于腹膜外间隙跨越输精管表面。继续直视下缝合内环口内侧壁和上壁腹膜组织,于最初进针处出针和打结,闭合内环口。结果292侧体外丝线牵拉冗厚腹膜后,缝针能顺利跨越精索血管、Doom三角区以及输精管表面。80例单侧手术时间(18.5±3.2)min,106例双侧手术时间(32.6±5.3)min。均无术中并发症发生,均在术后6 h内出院。122例术后随访3~18个月(平均8.5月),未出现切口感染、医源性隐睾或睾丸萎缩等并发症,无复发疝、鞘膜积液。结论对于内环皱褶冗厚的儿童斜疝,体外丝线牵拉法可有效展开冗厚的后腹膜,降低两孔法腹腔镜内环口缝扎时缝针跨越精索血管、Doom三角区以及输精管表面的难度,具有安全性、可行性。 展开更多
关键词 斜疝 腹膜皱褶冗厚 内环缝扎 Doom三角区 精索血管 输精管
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两种咔唑基-吡啶-N-氧化物内盐荧光极性探针研究
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作者 梁文娟 王慧敏 +1 位作者 白云峰 冯锋 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第6期1600-1606,共7页
合成了4-(9H-咔唑-9-基)吡啶1-氧化物(CPNO)和4-(4-(9H-咔唑-9-基)苯基)吡啶1-氧化物(CPPNO)两种咔唑基-吡啶-N-氧化物内盐,测定了它们在不同溶剂中的紫外-可见吸收和荧光光谱,均表现出对溶剂极性较好的敏感性。计算表明,两个化合物都... 合成了4-(9H-咔唑-9-基)吡啶1-氧化物(CPNO)和4-(4-(9H-咔唑-9-基)苯基)吡啶1-氧化物(CPPNO)两种咔唑基-吡啶-N-氧化物内盐,测定了它们在不同溶剂中的紫外-可见吸收和荧光光谱,均表现出对溶剂极性较好的敏感性。计算表明,两个化合物都具有较大的激发态偶极矩,是化合物溶剂极性敏感性的原因。研究为开发新型的荧光极性探针提供了一种新思路。 展开更多
关键词 咔唑基 吡啶 N氧化物内盐 溶剂效应 荧光极性探针
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内蒙古牧区畜产品销售新渠道建设与优化探究
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作者 刘小燕 图雅 《安徽农业科学》 CAS 2024年第9期203-205,225,共4页
畜牧业供给侧结构性改革以来,内蒙古按照“稳羊增牛扩猪禽”发展思路,调整优化生产结构和区域布局,聚焦绿色畜产品生产基地建设、优质畜产品有效供给,在畜产品产量继续提升的同时,销售量也持续增加。草原牧区是内蒙古畜产品主要来源地,... 畜牧业供给侧结构性改革以来,内蒙古按照“稳羊增牛扩猪禽”发展思路,调整优化生产结构和区域布局,聚焦绿色畜产品生产基地建设、优质畜产品有效供给,在畜产品产量继续提升的同时,销售量也持续增加。草原牧区是内蒙古畜产品主要来源地,在保障畜产品安全方面发挥着重要作用。目前牧区畜产品在销售渠道环节存在问题,畜产品的销售渠道不足,可供牧户选择的便捷、稳定、多样化的销售渠道比较少,因而影响了畜产品竞争力和收益的提升。牧区畜产品营销需要更具有针对性,把产地市场与消费地市场紧密结合起来,加快由“运牛羊”向“运肉”转变,缩短流通环节,最大程度降低销售成本。牧区畜产品销售渠道需向多元化、组织化、专业化、规模化、规范化的方向发展。 展开更多
关键词 销售渠道 畜产品 牧区 内蒙古
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海德格尔的元政治学和被隐蔽的“内在的真理”
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作者 朱清华 《同济大学学报(社会科学版)》 北大核心 2024年第2期76-84,102,共10页
近年研究证实海德格尔原始手稿中有“国家社会主义的内在真理”这样的表达。但这个发现并不能证明海德格尔哲学是纳粹政治学。“内在的真理”这个概念跟海德格尔这一时期构建元政治学的设想有关。作为区域的元存在论,元政治学要将存有... 近年研究证实海德格尔原始手稿中有“国家社会主义的内在真理”这样的表达。但这个发现并不能证明海德格尔哲学是纳粹政治学。“内在的真理”这个概念跟海德格尔这一时期构建元政治学的设想有关。作为区域的元存在论,元政治学要将存有的真理落实到存在者层面的政治活动中。而存在的真理则通过荷尔德林的诗显现为“亲密性”这一比希腊的■更为源初的概念。从海德格尔的元政治学理论构想来看,他是以“国家社会主义的内在真理”之名来构思他所认为的理想政治之基础,而非为任何现成的纳粹运动提供思想基础。他所谓的“精神的国家社会主义”指的并非现实政治中的国家社会主义,而是元政治学用来称呼它要促成的涉及民族和此在本质的运动的名称。元政治学的构想没有成功,并不表明海德格尔思想的失败。 展开更多
关键词 海德格尔 元政治学 内在的真理 亲密性
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开挖顺序及内支撑早期刚度对软土基坑稳定性影响规律
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作者 管大刚 胡志明 +3 位作者 郑鹏鹏 袁山 陈保国 张艳林 《建筑科学与工程学报》 CAS 北大核心 2024年第2期181-190,共10页
深基坑开挖变形控制是软土基坑工程的难题,工程中常采用密集的混凝土内支撑来提高支撑刚度,然而实际工程中未能合理考虑软土深基坑的开挖顺序和混凝土内支撑早期刚度影响,往往导致基坑实际变形远大于设计值。结合珠三角水资源配置工程... 深基坑开挖变形控制是软土基坑工程的难题,工程中常采用密集的混凝土内支撑来提高支撑刚度,然而实际工程中未能合理考虑软土深基坑的开挖顺序和混凝土内支撑早期刚度影响,往往导致基坑实际变形远大于设计值。结合珠三角水资源配置工程的软土深基坑,利用验证后的数值模拟方法研究了不同开挖顺序及混凝土内支撑早期刚度对基坑受力和变形特性的影响规律,得出了分层分区非对称开挖和对称开挖对地连墙水平位移和地表沉降的影响规律。结果表明:尽管非对称开挖会造成基坑两侧的地连墙位移和地表沉降差异,但是密集内支撑条件下非对称开挖比对称开挖对于基坑周围地表沉降和地连墙水平位移影响更小并能够大量节约工期;受混凝土内支撑早期刚度影响,施作内支撑后越早进入下一步开挖,地连墙水平位移和周围地表沉降越大;考虑内支撑早期刚度影响时基坑上部的内支撑轴力会增大,而下部的内支撑轴力会减小,早期刚度越小,这种趋势越明显;现场施工时难以实时动态监测混凝土的弹性模量,极易造成内支撑轴力的早期监测数据失真,甚至给工程带来错误决策。 展开更多
关键词 深基坑 软土 开挖顺序 混凝土内支撑 早期刚度 变形特性
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黄河内蒙古河段水文情势变化及生态效应初探
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作者 米玮洁 张舜 +2 位作者 胡俊 高少波 胡菊香 《水生态学杂志》 CSCD 北大核心 2024年第1期42-49,共8页
选择月均流量、日均流量变幅、极端流量和脉冲延时4个水文情势指标,采用IHA-RVA(水文情势变化指标-变化范围法)分析黄河干流内蒙古河段水文情势的时空变化特征,辨析黄河鱼类生态习性与径流组分的响应关系,探讨内蒙古河段流量过程、极端... 选择月均流量、日均流量变幅、极端流量和脉冲延时4个水文情势指标,采用IHA-RVA(水文情势变化指标-变化范围法)分析黄河干流内蒙古河段水文情势的时空变化特征,辨析黄河鱼类生态习性与径流组分的响应关系,探讨内蒙古河段流量过程、极端流量变化的生态效应。黄河干流上游河段水利工程运行后,内蒙古河段的水文情势明显改变,进而改变该河段的生态水文联系过程。黄河内蒙古河段枯水期月均流量增加(1、2月份月均流量增幅超过70%)、最小日均流量增加(石嘴山断面最小日流量增幅超过50%),保障了河道流水栖息生境,有利于鱼类越冬。该河段日均流量变幅降低,有利于粘性卵孵化。但是内蒙古河段汛期月均流量减小(7-10月份月均流量降幅接近50%),大、小洪水持续时间缩短,不利于扩展横向栖息地;最大流量出现时间在上游河段延迟超过2个月、在中下游河段提前约1个月,洪水脉冲刺激时间紊乱可能影响鱼类繁殖行为。研究可为黄河内蒙古河段鱼类栖息地保护以及上游水库生态调度提供技术支持。 展开更多
关键词 流量过程 水文情势 鱼类 生态效应 黄河内蒙古河段
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党建引领体育社会组织发展的内在逻辑与现实路径
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作者 朱萍 冯兴华 +2 位作者 龚博敏 蔡增亮 郑芬 《当代体育科技》 2024年第1期83-86,90,共5页
加强党组织建设是新时代推进体育社会组织自身发展和参与治理的根本所在,发挥党组织在体育社会组织建设中的战斗堡垒作用,将有助于将党的政治优势和组织优势切实注入体育社会治理全过程。在体育社会组织中,将党的领导这一显著优势和党... 加强党组织建设是新时代推进体育社会组织自身发展和参与治理的根本所在,发挥党组织在体育社会组织建设中的战斗堡垒作用,将有助于将党的政治优势和组织优势切实注入体育社会治理全过程。在体育社会组织中,将党的领导这一显著优势和党的建设这一关键环节融入体育社会组织的革新、组织、运行、发展,可切实解决当前体育社会组织面临的发展自主性不足、服务硬实力不强、社会认可度不高等瓶颈问题。在党建引领下,凸显党组织的政治逻辑、组织逻辑、民本逻辑,推进体育社会组织思想作风优化、提升社会动员能力、强化社会责任担当,注入人民性、规范性、协同性,推进群众化、制度化、多元化发展,将有力推动体育社会组织治理效能的进一步提升,为全民健身和体育治理作出积极贡献。 展开更多
关键词 党建 体育社会组织 内在逻辑 现实路径
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