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Spatial-temporal differentiation and influencing factors of rural settlements in mountainous areas: an example of Liangshan Yi Autonomous Prefecture, Southwestern China

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Journal of Mountain Science 2024年第1期21卷 218-235页

作者： WANG Yumeng DENG Qingchun YANG haiqing LIU Hui YANG Feng ZHAO Yakai School of Geographical Sciences China West Normal UniversityNanchong 637009China Sichuan Provincial Engineering Laboratory of Monitoring and Control for Soil Erosion in Dry Valleys China West Normal UniversityNanchong 637009China Liangshan Soil Erosion and Ecological Restoration in Dry Valleys Observation and Research Station Xide 616753China

Rural settlement is the basic spatial unit for compact communities in rural area. Scientific exploration of spatial-temporal differentiation and its influencing factors is the premise of spatial layout rationalization. Based on land use data of Liangshan Yi Autonomous Prefecture(hereinafter referred to as Liangshan Prefecture) in Sichuan Province, China from 1980 to 2020, compactness index, fractal dimension, imbalance index, location entropy and the optimal parameters-based geographical detector(OPGD) model are used to analyze the spatial-temporal evolution of the morphological characteristics of rural settlements, and to explore the influence of natural geographical factors, socioeconomic factors, and policy factors on the spatial differentiation of rural settlements. The results show that:(1) From 1980 to 2020, the rural settlements area in Liangshan Prefecture increased by 15.96 km^(2). In space, the rural settlements are generally distributed in a local aggregation, dense in the middle and sparse around the periphery. In 2015, the spatial density and expansion index of rural settlements reached the peak.(2) From 1980 to 2020, the compactness index decreased from 0.7636 to 0.7496, the fractal dimension increased from 1.0283 to 1.0314, and the fragmentation index decreased from 0.1183 to 0.1047. The spatial morphological structure of rural settlements tended to be loose, the shape contour tended to be complex, the degree of fragmentation decreased, and the spatial distribution was significantly imbalanced.(3) The results of OPGD detection in 2015 show that the influence of each factor is slope(0.2371) > traffic accessibility(0.2098) > population(0.1403) > regional GDP(0.1325) > elevation(0.0987) > poverty alleviation(0). The results of OPGD detection in 2020 show that the influence of each factor is slope(0.2339) > traffic accessibility(0.2198) > population(0.1432) > regional GDP(0.1219) > poverty alleviation(0.0992) > elevation(0.093). Natural geographical facto

关键词： Rural settlements Location entropy Geographical detector Spatiotemporal differentiation Influencing factors

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Evaluation of the Oxidation Reactivity and Behavior of Exhaust Soot Particles from Diesel Engines with Different Emission Levels

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 72-80页

作者： Wang Yajun Lin Lei Xing Jianqiang LüXu Yang He Song haiqing SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China State Key Laboratory of Engines Tianjin UniversityTianjin 300072China

The aim of this study was to investigate the oxidation reactivity and behavior of exhaust particulate matter(PM)from diesel *** samples from two diesel engines(1K,CY4102)with different emission levels were collected by a thermophoretic system and a quartz *** oxidation reactivity,oxidation behaviors,and physicochemical properties of the PM samples were analyzed using thermogravimetric analysis(TGA),high-resolution transmission electron microscopy(HRTEM),Fourier-transform infrared spectrometry(FTIR),and Raman *** results showed that there was a great difference in the oxidation reactivity of soot particles emitted by the two different diesel engines.A qualitative analysis of the factors influencing oxidation reactivity showed that the nanostructure,degree of graphitization,and relative concentration of aliphatic C—H functional groups were the most important factors,whereas no significant correlation was found between the primary particle size and activation energy of the diesel *** on the oxidation behavior analysis,the diesel soot particles exhibited both internal and surface oxidation modes during the oxidation *** oxidation was dominant during the initial stage,and as oxidation progressed,the mode gradually changed to internal *** oxidation mode of soot particles from the 1K engine was significantly higher than that of CY4102.

关键词： diesel engine soot particles oxidation reactivity oxidation behavior

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聚丙烯塑料涂料的制备与性能研究

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涂料工业 2000年第4期30卷 1-4页

作者：周海清周铭郑州大学化学化工学院 450052 常州涂料化工研究院 213016

利用接枝共聚反应合成了在聚丙烯塑料表面具有优异附着力的氯化聚丙烯改性树脂 ,对该树脂的结构、性能进行了讨论 ,同时对该树脂在聚丙烯表面的附着机理进行了探讨。利用该氯化聚丙烯改性树脂配制的底面合一涂料 ,具有较好的综合性能 ,... 详细信息

利用接枝共聚反应合成了在聚丙烯塑料表面具有优异附着力的氯化聚丙烯改性树脂 ,对该树脂的结构、性能进行了讨论 ,同时对该树脂在聚丙烯表面的附着机理进行了探讨。利用该氯化聚丙烯改性树脂配制的底面合一涂料 ,具有较好的综合性能 ,适合汽车等聚丙烯塑料件的涂装。

关键词：聚丙烯塑料涂料制备性能接枝共聚

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Integrating phosphorus management and cropping technology for sustainable maize production

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Journal of Integrative Agriculture 2024年第4期23卷 1369-1380页

作者： haiqing Gong Yue Xiang Jiechen Wu Laichao Luo Xiaohui Chen Xiaoqiang Jiao Chen Chen State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Department of Sustainable Development Environmental Science and Engineering(SEED)KTH Royal Institute of TechnologyStockholm SE-10044Sweden Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention School of Resources and EnvironmentAnhui Agricultural UniversityHefei 230036China Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering National Observations and Research Station for Wetland Ecosystems of the Yangtze EstuaryInstitute of Biodiversity Science and Institute of Eco-ChongmingCollege of Life SciencesFudan UniversityShanghai 200438China

Achieving high maize yields and efficient phosphorus(P)use with limited environmental impacts is one of the greatest challenges in sustainable maize *** plant density is considered an effective approach for achieving high maize ***,the low mobility of P in soils and the scarcity of natural P resources have hindered the development of methods that can simultaneously optimize P use and mitigate the P-related environmental footprint at high plant *** this study,meta-analysis and substance flow analysis were conducted to evaluate the effects of different types of mineral P fertilizer on maize yield at varying plant densities and assess the flow of P from rock phosphate mining to P fertilizer use for maize production in China.A significantly higher yield was obtained at higher plant densities than at lower plant *** application of single superphosphate,triple super-phosphate,and calcium magnesium phosphate at high plant densities resulted in higher yields and a smaller environmental footprint than the application of diammonium phosphate and monoammonium *** scenario analyses suggest that combining the optimal P type and application rate with a high plant density could increase maize yield by 22%.Further,the P resource use efficiency throughout the P supply chain increased by 39%,whereas the P-related environmental footprint decreased by 33%.Thus,simultaneously optimizing the P type and application rate at high plant densities achieved multiple objectives during maize production,indicating that combining P management with cropping techniques is a practical approach to sustainable maize *** findings offer strategic,synergistic options for achieving sustainable agricultural development.

关键词： maize plant density mineral phosphorus fertilizer meta-analysis substance flow analysis

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Anchoring Ru clusters to highly defective N-doped carbon nanotubes via a thermal-shock strategy for stable industrial hydrogen evolution

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Nano Research 2024年第6期17卷 5261-5269页

作者： Zhiming Li Xinyu Li haiqing Ma Chenliang Ye Hongan Yu Long Nie Meng Zheng Jin Wang College of Materials Science and Engineering Shenzhen UniversityShenzhen 518060China School of Chemistry and Materials Science Anhui Normal UniversityWuhu 241002China Department of Power Engineering North China Electric Power UniversityBaoding 071003China

Non-Pt or low-Pt catalysts capable for stable generation of hydrogen via water electrolysis at an industrial level of current density are highly *** of strong metal-support connection is beneficial to improve the performance stability of *** we employed highly defective N-doped carbon nanotubes(d-N-CNT)as the support to achieve uniform and firm anchoring of Ru clusters(~1.9 nm)via a thermal-shock *** as-prepared Ru/d-N-CNT catalyst shows excellent catalytic activity for hydrogen evolution reaction(HER)in alkaline media and requires an overpotential(ƞ)of 12 mV at 10 mA·cm^(−2)and 116 mV at 200 mA·cm^(−2)with a Ru loading of 0.025 mg·cm^(−2).Impressively,Ru/d-N-CNT presents robust stability for HER at both low current density(stable for at least 1000 h at 10 mA·cm^(−2))and the industrial level of current density(stable for at least 100 h at 1000 mA·cm^(−2)),remarkably outperforming commercial Pt/C and Ru/*** highly defective nature of the N-CNT support endowed the as-prepared Ru/d-N-CNT catalyst with strong metal-support adhesion that efficiently suppressed agglomeration as well as obscission of Ru ***,the rich defects increased the surface energy of the N-CNT support and resulted in improved hydrophilicity as evidenced by the liquid contact angle measurement and the bubble evolution process,which also played an important role in stabilizing the HER performance especially at large current density.

关键词： thermal-shock method hydrogen evolution reaction large-current-density Ru cluster

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非饱和土的非线性模型及其应用

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岩土工程学报 1999年第5期21卷 603-608页

作者：陈正汉周海清 DGFredlund 后勤工程学院重庆400041 加拿大Saskatchewan大学

提出了一个较完整的非饱和土的非线性模型。该模型涉及土的变形和水量变化两个方面，共包含１３个参数。测定全部参数只需用两种三轴试验。应用所提模型预估三轴不排水试验中的吸力变化，理论计算与试验结果比较接近。

关键词：非饱和土非线性模型三轴剪切试验

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High-frequency repetitive transcranial magnetic stimulation promotes neural stem cell proliferation after ischemic stroke

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Neural Regeneration Research 2024年第8期19卷 1772-1780页

作者： Jing Luo Yuan Feng Zhongqiu Hong Mingyu Yin haiqing Zheng Liying Zhang Xiquan Hu Department of Rehabilitation Medicine The Third Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Department of Hepatobiliary Surgery The Third Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

Prolife ration of neural stem cells is crucial for promoting neuronal regeneration and repairing cerebral infarction *** magnetic stimulation(TMS)has recently emerged as a tool for inducing endogenous neural stem cell regeneration,but its underlying mechanisms remain unclea r In this study,we found that repetitive TMS effectively promotes the proliferation of oxygen-glucose deprived neural stem ***,repetitive TMS reduced the volume of cerebral infa rction in a rat model of ischemic stro ke caused by middle cerebral artery occlusion,im p roved rat cognitive function,and promoted the proliferation of neural stem cells in the ischemic ***-sequencing found that repetitive TMS activated the Wnt signaling pathway in the ischemic penumbra of rats with cerebral ***,PCR analysis revealed that repetitive TMS promoted AKT phosphorylation,leading to an increase in mRNA levels of cell cycle-related proteins such as Cdk2 and *** effect was also associated with activation of the glycogen synthase kinase 3β/β-catenin signaling pathway,which ultimately promotes the prolife ration of neural stem ***,we validated the effect of repetitive TMS on AKT *** found that repetitive TMS promoted Ca2+influx into neural stem cells by activating the P2 calcium channel/calmodulin pathway,thereby promoting AKT phosphorylation and activating the glycogen synthase kinase 3β/β-catenin *** findings indicate that repetitive TMS can promote the proliferation of endogenous neural stem cells through a Ca2+influx-dependent phosphorylated AKT/glycogen synthase kinase 3β/β-catenin signaling *** study has produced pioneering res ults on the intrinsic mechanism of repetitive TMS to promote neural function recove ry after ischemic stro *** results provide a stro ng scientific foundation for the clinical application of repetitive ***,repetitive TMS treatment may not only be an efficient an

关键词： AKT/β-catenin signaling brain stimulation Ca2+influx cell proliferation ischemic stroke middle cerebral artery occlusion neural stem cells neurological rehabilitation repetitive transcranial magnetic stimulation

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LncRNA HOTAIR promotes DNA damage repair and radioresistance by targeting ATR in colorectal cancer

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Oncology Research 2024年第8期32卷 1335-1346页

作者： haiqing HU HAO YANG SHUAISHUAI FAN XUE JIA YING ZHAO HONGRUI LI Department of Endoscopic Center Peking University Cancer Hospital(Inner Mongolia Campus)&Affiliated Cancer Hospital of Inner Mongolia Medical UniversityHuhhot010020China Department of Radiation Oncology Peking University Cancer Hospital(Inner Mongolia Campus)&Affiliated Cancer Hospital of Inner Mongolia Medical UniversityKey Laboratory of Radiation Physics and Biology of Inner Mongolia Medical UniversityPeking University Cancer Hospital(Inner Mongolia Campus)&Affiliated Cancer Hospital of Inner Mongolia Medical UniversityHuhhot010020China Graduate School Inner Mongolia Medical UniversityHuhhot010020China

Long non-coding RNAs(lncRNAs)have been implicated in cancer progression and drug resistance ***,there is evidence that lncRNA HOX transcript antisense intergenic RNA(HOTAIR)is involved in colorectal cancer(CRC)*** present study aimed to examine the functional role of lncRNA HOTAIR in conferring radiotherapy resistance in CRC cells,as well as the underlying *** relative expression levels of HOTAIR were examined in 70 pairs of CRC tumor and para-cancerous tissues,as well as in radiosensitive and radioresistant *** correlations between HOTAIR expression levels and clinical features of patients with CRC were assessed using the Chi-square *** assays such as cell proliferation,colony formation and apoptosis assays were conducted to determine the radiosensitivity in CRC cells with HOTAIR silencing after treatment with different doses of *** pull-down assay andﬂuorescence in situ hybridization(FISH)were used to determine the interaction between HOTAIR and DNA damage response mediator ataxia-telangiectasia mutated-and Rad3-related(ATR).HOTAIR was signiﬁcantly upregulated in CRC tumor tissues,especially in radioresistant tumor *** elevated expression of HOTAIR was correlated with more advanced histological grades,distance metastasis and the poor prognosis in patients with *** HOTAIR suppressed the proliferation and promoted apoptosis and radiosensitivity in CRC *** knockdown also inhibited the tumorigenesis of CRC cells and enhanced the sensitivity to radiotherapy in a mouse xenograft ***,the data showed that HOTAIR could interact with ATR to regulate the DNA damage repair signaling *** HOTAIR impaired the ATR-ATR interacting protein(ATRIP)complex and signaling in cell cycle ***,the present results indicate that lncRNA HOTAIR facilitates the DNA damage response pathway and promotes radioresistance in CRC cells by targeting ATR.

关键词： LncRNA HOTAIR CRC radioresistance DNA damage repair ATR

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Induced electric fields and plasmonic interactions between a metallic nanotube and a thin metallic film

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Science China(Physics,Mechanics & Astronomy) 2010年第1期53卷 38-43页

作者： LI HongJian 1,2 , FU ShaoLi 1 , XIE SuXia 1,2 , XU haiqing 1 , zhou Xin 1,2 & WU JinJun 1 1 College of Physics Science and Technology, Central South University, Changsha 410083, China 2 College of Materials Science and Engineering, Central South University, Changsha 410083, China College of Physics Science and Technology Central South University Changsha China College of Materials Science and Engineering Central South University Changsha China

We have numerically simulated the induced electric fields and the plasmonic interactions of a metallic nanotube near a thin metallic film. Our study shows that the energies and intensities of the plasmon resonances depend strongly on the aspect ratio (the ratio of the inner to outer radius) of the nanotube as well as the separation between the center of the nanotube and the upper surface of the metallic film and the thickness of the film. The enhancement of the induced electric field of this system reaches as high as 10 4 orders of magnitude and its field distribution is characterized by waveguide-mode resonance. The report proposes that these phenomena can be applied to designing surface enhanced spectroscopies such as surface enhanced Raman spectroscopy for efficient chemical and biological sensing.

关键词： metallic nanotube virtual state plasmons extinction spectrum

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内嵌CLIPS推理引擎的中文专家系统开发工具及其在厦门市深基坑支护结构选型专家系统中的应用

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岩石力学与工程学报 2002年第A2期21卷 2558-2561页

作者：周海清王权明陈正汉解放军后勤工程学院建筑工程系重庆400041 厦门市建委厦门361000

采用面向对象方法,将CLIPS的C++包装类引入自行研制的中文专家系统开发工具CESDT内,实现了在此工具内无缝嵌入CLIPS推理引擎。并用此工具开发了厦门市深基坑支护结构选型专家系统。

关键词：计算机技术 CLIPS 专家系统 Visual C++编程

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