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Unique landslides (loess slide-flows) induced by an extreme rainstorm in 2018 on the Loess Plateau: A new geological hazard and erosion process

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International Journal of Sediment Research 2023年第2期38卷 228-239页

作者： Li Luo Wen-Zhao Guo Pei Tian Yi-li Liu shao-kun wang Jia-Wei Luo State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau/College of Water Resources and Architectural Engineering Northwest Agriculture and Forestry University State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province Central China Normal University

Currently, the vegetation has recovered well in most areas of the Loess Plateau in China, and soil erosion has significantly decreased. However, the heavy rainfall event in July 2018 triggered many instances of a unique type of loess landslides(i.e., slide-flows) on the gully-slopes with vegetation recovery in the Nanxiaohegou Basin on the Loess Plateau. This rainfall event was unusual and was a persistent heavy rainfall. The accumulated rainfall from 24 June to 10 July was 232.2 mm, which comprised 42% of the mean annual rainfall. A loess slide-flow is characterized by combining two movement types of the slide and flow. The loess slide-flows first slide on the gully-slopes and then turn into long run-out earthflows moving downstream, delivering vast amounts of sediment to the river. The average landslide erosion rates were 110.8-134.9 kg/m2. These loess slide-flows generally did not occur individually but in groups,which were characterized by large numbers, high density, small scale, and shallow depth. The changes of vegetation characteristics and soil characteristics both had a significant impact on the scale of the landslides. Grass with high coverage had an adverse effect on the occurrence of shallow landslides. The adverse hydrological effects of the plant may offset the weak root reinforcement. Loess slide-flows have become a new geological hazard and erosion process on the Loess Plateau. Loess slide-flows are a prominent ecological and environmental problem after vegetation restoration, and more attention should be paid to loess slide-flows in the future.

关键词： Loess plateau Landslide Soil erosion Vegetation Rainfall

Theoretical Study of the Thermal Decomposition of Chlorofluoromethanol (CHClFOH)

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Chinese Chemical Letters 2000年第10期11卷 891-892页

作者： shao kun wang Hua HOU Qing Zhu ZHANG Chun Yan KONG Bao Shan wang Yue Shu Gu School of Chemistry Shandong UniversityJinan 250100 Department of Chemistry Dezhou Normal special schoolDezhou 253023

A complete potential energy surface for the CHClFOH system was calculated at the G3(MP2) level. The calculations reveal that the four-center 1,2-HX (X = F, Cl) elimination mechanism rather than the bond scission mechanism dominate decomposition of CHClFOH. The results are valuable to understand the atmospheric chemistry of HCFC-31.

关键词： chlorofluoromethanol reaction mechanism potential energy surface

Structural evolution and high-temperature sensing performance of polymer-derived SiAlBCN ceramics

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Journal of Advanced Ceramics 2024年第4期13卷 478-485页

作者： Chao Ma kun Liu Pengfei shao Daoyang Han Kang wang Mengmeng Yang Rui Zhao Hailong wang Rui Zhang Gang shao School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Zhongyuan Critical Metal Laboratory Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentZhengzhou UniversityZhengzhou 450002China

In situ temperature monitoring has become extremely imperative in high-temperature harsh environments and polymer-derived ceramics(PDCs)as sensing materials have attracted great ***,the stability and oxidation/corrosion resistance of PDCs cannot be simultaneously achieved at the moment,limiting their practical ***,polymer-derived SiAlBCN ceramics were synthesized via polymer conversion method under different pyrolysis *** microstructure evolution,high temperature sensing properties,and stability were investigated in *** results show that the amorphous SiAlBCN phase grows more orderly and the size of the free carbon phase enlarges with the increasing *** defect concentration displays a decreasing ***,the SiAlBCN ceramics as sensing materials exhibit a good temperature-resistance property from roo temperature to 1100℃.The fabricated SiAlBCN temperature sensor possesses excellent stability,repeatability,and ***,SiAlBCN ceramics exhibit distinguished oxidation/corrosion resistance after 100 h treatment at 1200℃in a water/oxygen environment,which is attributed to their low corrosive rate constant(0.57 mg/(cm^(2)·h))and oxidative rate constant(3.43 mg^(2)/(cm^(4)·h)).Therefore,polymer-derived SiAlBCN ceramics as sensing materials,which possess outstanding stability and oxidation/corrosion resistance,have great potential for in-situ monitoring of extreme environmental temperatures in the future.

关键词： polymer-derived SiAlBCN ceramics temperature sensor harsh environments oxidation and corrosion resistance

Room-temperature and atmospheric-pressure hydrogenation of lignin-derived phenol to KA oil by Pt/NiO@MOFs

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Nano Research 2024年第8期17卷 7053-7060页

作者： Fengbin Zheng kun wang Yifei Ren Bohua wang Wenxing Chen Caoyu Yang Shengxian shao Yinglong wang Zhiyong Tang Guodong Li College of Chemical Engineering Qingdao University of Science and TechnologyQingdao 266042China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100181China School of Nanoscience and Technology University of Chinese Academy of SciencesBeijing 100049China

Hydrogenation of lignin-derived phenol to KA oil(the mixture of cyclohexanone(K)and cyclohexanol(A))is attractive yet challenging in the sustainable upgrading of biomass derivatives under mild *** supported metal catalysts have been widely studied but the active components on supports often exhibit low recyclability due to their instability under experimental *** we show fabricating ultrasmall Pt/NiO in the pores of chromium terephthalate MIL-101 as catalysts for hydrogenation of ***,Pt/NiO@MIL-101 achieves catalytic phenol hydrogenation to KA oils of tunable K/A ratios and good reusability under room temperature and atmospheric hydrogen pressure,superior to contrast Pt@MIL-101 and Pt/NiO *** excellent performance mainly originates from the effective adsorption and activation of phenol by coordinatively unsaturated Cr sites and H2 activation on ultrasmall Pt/NiO as well as its effective spillover to the adsorbed phenol over Cr sites for hydrogenation ***,such catalyst also displays the excellent performances for hydrogenation of phenol’s derivatives under mild conditions.

关键词： ultrasmall Pt/NiO MIL-101 phenol hydrogenation KA oil

D609 induces vascular endothelial cells and marrow stromal cells differentiation into neuron-like cells

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Acta Pharmacologica Sinica 2004年第4期25卷 44-48页

作者： Nan wang, Chun-qing DU, shao-shan wang, kun XIE, Shang-li ZHANG, Jun-ying MIAO2 Institute of Developmental Biology, School of Life Science, Shandong University, Ji-nan 250100, China Institute of Developmental Biology School of Life Science Shandong University Jinan 250100

AIM: To investigate the effect of tricyclodecane-9-yl-xanthogenate (D609) on cell differentiation in vascular endo- thelial cells (VECs) and marrow stromal cells (MSCs). METHODS: Morphological changes were observed under phase contrast microscope. Electron microscope and immunostaining were used for VECs identification. The expressions of neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP) were examined by immunohistochemistry. RESULTS: After 6 h of induction with D609, some VECs showed morphological changes characteristic of neurones. 9 h later, more VECs became neuron-like cells. About 30.8 % of VECs displayed positive NSE (P<0.01), while the expression of GFAP was negative. When MSCs were exposed to D609, the cells displayed neuronal morphologies, such as pyramidal cell bodies and processes formed extensive networks at 3 h. 6 h later, almost all of the cells exhibited a typical neuronal appearance, and 85.6 % of MSCs displayed intensive positive NSE, but GFAP did not express. CONCLUSION: D609 induces VECs and MSCs differentiation into neuron-like cells.

关键词： tricyclodecane-9-yl-xanthogenate cell differentiation vascular endothelial cells marrow stromal cells neuron-like cells

Technologies and studies of gas exchange in two-stroke aircraft piston engine:A review

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Chinese Journal of Aeronautics 2024年第1期37卷 24-50页

作者： Yu ZHOU Xueyu LI Shuiting DING Shuai ZHAO kun ZHU Longtao shao Farong DU Gerui wang Zheng XU Research Institute of Aero-Engine Beihang UniversityBeijing 100191China Aircraft/Engine Integrated System Safety Beijing Key Laboratory Beijing 100191China School of Transportation Science and Engineering Beihang UniversityBeijing 100191China Civil Aviation University of China Tianjin 300300China Aero Engine Academy of China Beijing 101304China School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beihang Hangzhou Innovation Institute Yuhang Hangzhou 310052China

The in-cylinder gas exchange process is crucial to the power performance of two-stroke aircraft piston engines,which is easily influenced by complex factors such as high-altitude performance variation and in-cylinder flow *** paper reviews the development history and characteristics of gas exchange types,as well as the current state of theory and the validation methods of gas exchange technology,while also discusses the trends of cutting-edge technologies in the *** paper provides a theoretical foundation for the optimization and engineering design of gas exchange systems and,more importantly,points out that the innovation of gas exchange types,the modification of theoretical models,and the technology of variable airflow organization are the key future research directions in this field.

关键词： Aircraft piston engine Aircraft power systems Gas exchange High-altitude performance In-cylinder flow Two-stroke Unmanned Aerial Vehicles(UAVs)

Characteristics of deep drainage and soil water in the mobile sandy lands of Inner Mongolia, northern China

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Journal of Arid Land 2015年第2期7卷 238-250页

作者： Xin Ping LIU Yu Hui HE Xue Yong ZHAO Tong Hui ZHANG La Mei ZHANG Yun Hua MA Shu Xia YAO shao kun wang Shui Lian WEI Naiman Desertification Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Laboratory of Stress Ecophysiology and Biotechnology Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

Quantification of deep drainage and the response of soil water content to rainfall patterns are critical for an effective management strategy of soil water conservation and groundwater utilization. However, there has been little information on how rainfall characteristics influence soil water dynamics and deep drainage in mobile sandy lands. We used an underground chamber to examine the responses of deep drainage and soil water content in mobile sandy lands to rainfall characteristics in Inner Mongolia during the growing seasons of 2010, 2011 and 2012. Results showed that rainfall in this area was dominated by small events （〈5 mm）, which increased soil water con- tent in the surface soil layers （0-40 cm）, but did not increase soil water content in the deeper soil layers （greater than 40 cm）. Soil water content at the 0-100 cm depth increased significantly when the total amount of rain was 〉20 mm. Rainfall amount, intensity and the duration of dry intervals were significantly related to the soil water content in different soil layers. Deep drainage was significantly correlated with rainfall amount and intensity, but not with the duration of dry intervals. The coefficients of deep drainage in the mobile sandy lands ranged from 61.30% to 67.94% during the growing seasons. Our results suggested that rainfall infiltration in the mobile sandy lands had considerable potential to increase soil water storage while recharging the groundwater in this region.

关键词： mobile sandy lands rainfall characteristics deep drainage soil water content

A GMM approach in coupling internal data and external summary information with heterogeneous data populations

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Science China Mathematics 2024年第5期67卷 1115-1132页

作者： Jun shao Jinyi wang Lei wang Key Laboratory of Advanced Theory and Application in Statistics and Data Science(East China Normal University) Ministry of EducationShanghai 200062China School of Statistics East China Normal UniversityShanghai 200062China Department of Statistics University of Wisconsin-MadisonWI 53706USA School of Statistics and Data Science KLMDASRLEBPS and LPMCNankai UniversityTianjin 300071China

Because of advances in data collection and storage,statistical analysis in modern scientific research and practice now has opportunities to utilize external information such as summary statistics from similar studies.A likelihood approach based on a parametric model assumption has been developed in the literature to utilize external summary information when the populations for external and main internal data are assumed to be the *** this article,we instead consider the generalized estimation equation(GEE)approach for statistical inference,which is semiparametric or nonparametric,and show how to utilize external summary information even when internal and external data populations are not the *** approach is coupling the internal data and external summary information to form additional estimation equations and then applying the generalized method of moments(GMM).We show that the proposed GMM estimator is asymptotically normal and,under some conditions,is more efficient than the GEE estimator without using external summary *** of the asymptotic covariance matrix of the GMM estimators are also *** results are obtained to confirm our theory and quantify the improvements by utilizing external *** example is also included for illustration.

关键词： adjustment for heterogeneity constraint data integration generalized method of moments summarystatistic

Theoretical Studies on CH_3SiH_3+H→CH_3SiH_2+H_2 Reaction with the Variational Transitional State Theory

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Chinese Chemical Letters 2000年第2期11卷 119-122页

作者： Qing Zhu ZHANG Chuan Pu LIU shao kun wang Xin Ji XIE Miao ZHANG Yue She GU (School of Chemistry. State Key Laboratory of Crystal Materials, Shandong University Jinan 250100) School of Chemistry State Key Lab. of Crystal Materials Shandong University Jinan 250100 China

In this paper. the abstraction reaction of CH_3SiH_3 with H has been studied by using the 'direct dynamics' method of variational transition-state theory. which is based on the information on geometries. frequencies and energies calculalcd by ab inito along the minimum energy path. The rate constants of the title reaction were calculated for the range of temperature 298-1700 K. The rate constants calculated match well with the experimental values.

关键词： Variational transition state tunneling effect rate constants.