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| 1 | Grain-size characteristics of linear dunes on the northern margin of Qarhan Salt Lake, northwestern China显示文摘In order to clarify the formation mechanism of linear dunes on the northern margin of Qarhan Salt Lake, northwestern China, we analyzed the grain-size and sorting parameters of the dune and interdune sands. The surface sands(0–30 mm) from the dune base to the crest of both flanks and interdune corridors were sampled along transects from upwind to downwind through the dune field. The results indicated that the grain-size distribution differed at different positions between and within the dunes. The frequency curve for dune sands mainly showed a bimodal distribution, while the interdune sediments showed a trimodal distribution. The grain size distribution of the linear dunes showed a finer crest pattern, i.e. the crests were composed of sands that were generally finer, better sorted than those of base sands. In addition, at the dune field scale, the dune crest sands were tending to become much finer but sorting became worse along the downwind transects. However, the grain-size parameters of sediments in the interdune corridors showed no clear pattern. The results demonstrated that the grain size and sorting parameters exhibited a systematic change not only at the individual scale but also at the dune field scale. Our results quantitatively estimate the limited role of cohesive sediments on the formation of linear dune under unidirectional wind regime. More attention should be paid to a long-term wind regime observation, internal sedimentary structures and their formation ages. | LI Jiyan DONG Zhibao ZHANG Zhengcai QIAN Guangqiang LUO Wanyin LU Junfeng | 2015 | Journal of Arid Land2015，7，4： | 13 |
| 2 | Environmental Adaptive Control of a Snake-like Robot With Variable Stiffness Actuators显示文摘This work investigates adaptive stiffness control and motion optimization of a snake-like robot with variable stiffness actuators. The robot can vary its stiffness by controlling magnetorheological fluid(MRF) around actuators. In order to improve the robot's physical stability in complex environments, this work proposes an adaptive stiffness control strategy. This strategy is also useful for the robot to avoid disturbing caused by emergency situations such as collisions. In addition, to obtain optimal stiffness and reduce energy consumption, both torques of actuators and stiffness of the MRF braker are considered and optimized by using an evolutionary optimization algorithm. Simulations and experiments are conducted to verify the proposed adaptive stiffness control and optimization methods for a variable stiffness snake-like robots. | Dong Zhang Hao Yuan Zhengcai Cao | 2020 | IEEE/CAA Journal of Automatica Sinica2020，7，3： | 11 |
| 3 | Notoginsenoside Ft1 acts as a TGR5 agonist but FXR antagonist to alleviate high fat diet-induced obesity and insulin resistance in mice显示文摘Obesity and its associated complications are highly related to a current public health crisis around the world.A growing body of evidence has indicated that G-protein coupled bile acid(BA) receptor TGR5(also known as Gpbar-1) is a potential drug target to treat obesity and associated metabolic disorders.We have identified notoginsenoside Ftl(Ftl) from Panax notoginseng as an agonist of TGR5 in vitro.However,the pharmacological effects of Ftl on diet-induced obese(DIO) mice and the underlying mechanisms are still elusive.Here we show that Ftl(100 mg/100 diet) increased adipose lipolysis,promoted fat browning in inguinal adipose tissue and induced glucagon-like peptide-1(GLP-1) secretion in the ileum of wild type but not Tgr5^(-/-) obese mice.In addition,Ftl elevated serum free and taurineconjugated bile acids(BAs) by antagonizing Fxr transcriptional activities in the ileum to activate Tgr5 in the adipose tissues.The metabolic benefits of Ftl were abolished in Cyp27 al^(-/-) mice which have much lower BA levels.These results identify Ftl as a single compound with opposite activities on two key BA receptors to alleviate high fat diet-induced obesity and insulin resistance in mice. | Lili Ding Qiaoling Yang Eryun Zhang Yangmeng Wang Siming Sun Yingbo Yang Tong Tian Zhengcai Ju Linshan Jiang Xunjiang Wang Zhengtao Wang Wendong Huang Li Yang | 2021 | Acta Pharmaceutica Sinica B2021，11，6： | 10 |
| 4 | Aeolian transport over a developing transverse dune显示文摘The spatial and temporal changes in aeolian transport over a dune are fundamental factors that control the morphology of the dune.In the present study,we obtained direct field observations of aeolian transport over a developing transverse dune at the Shapotou Aeolian Experiment Site in the southeastern part of China’s Tengger Desert.The transport rate versus wind speed relationship is complicated over a developing dune compared with the relationships over flat surfaces and over dunes that are in equilibrium with the wind.We obtained trend lines for transport rate over the transverse dune versus distance.The transport rate generally increased from the toe to the crest above the stoss slope,but the difference in transport rate between the crest and the toe was smaller than those that have been proposed for taller dunes.The crest/toe ratio for transport rates therefore seems to depend greatly on dune height.Flux density profiles for different points above the dune at different wind speeds were well described by the exponential decay law,as has been proposed for saltation flux density profiles.Coefficients in the flux density profile function can be defined in terms of the transport rate and wind speed.However,the dependence of relative decay rate with height and average saltation height on wind speed was weaker than that observed in a wind tunnel and above a flat surface.The preliminary results obtained in this study require more evidence from field observations to fully describe aeolian transport above developing dunes. | ZhiBao DONG Ping LV ZhengCai ZHANG JunFeng LU | 2014 | Journal of Arid Land2014，6，3： | 7 |
| 5 | 为细菌的房间的一个非凡的紧、敏感的光可切换的基因表达式系统显示文摘 | Chen, Xianjun Liu, Renmei Ma, Zhengcai Xu, Xiaopei Zhang, Haoqian Xu, Jianhe Ouyang, Qi Yang, Yi | 2016 | Cell Research2016，26，7： | 7 |
| 6 | Pattern analysis of a linear dune field on the northern margin of Qarhan Salt Lake,northwestern China显示文摘In terms of formation mechanisms of linear dunes,there are open arguments for their widespread distribution and multi-morphological diversities.In order to clarify the formation mechanism of linear dunes of Qarhan Salt Lake,we used pattern analysis method to analyze the statistical characteristics and spatial variation of their pattern parameters.Except at the west-northwest margin,the pattern parameters showed regular spatial variation from the up-middle part towards the downwind end of the dune field.Based on the cumulative probability plots for inter-crest spacing and crest length,we divided the linear dunes into three groups,which corresponding to the three evolution stages of these dunes.The first group comprises erosional relics,with shorter crests,smaller inter-crest spacing and more random dune orientation.The second group comprises dunes whose sand supply is just sufficient to maintain stability and these dunes are approaching the net erosion stage.The crest length and inter-crest spacing of these dunes are much larger than those of the first group,and dune orientation is closer to the resultant drift direction (RDD) .The last group comprises linear dunes that are still undergoing vertical accretion and longitudinal elongation,which follows the RDD of the modern wind regime.The presence of regular spatial variation of pattern parameters and a similar geometry with the vegetated linear dunes suggest that deposition and erosion coexist in the development and evolution of linear dunes of Qarhan Salt Lake,i.e.deposition predominates at the downwind end of linear dunes in the vertical accretion and longitudinal elongation stage,whereas erosion mainly occurs at the upwind end of linear dunes in the degradation stage.Therefore,the formation mechanism of linear dunes in Qarhan Salt Lake can be reasonably explained by the combination of depositional and erosional theories. | LI Jiyan DONG Zhibao QIAN Guangqiang ZHANG Zhengcai LUO Wanyin LU Junfeng WANG Meng | 2016 | Journal of Arid Land2016，8，5： | 6 |
| 7 | Synthesis of 3,5-Dichloro-4-(1,1,2,2-tetrafluoroethoxy)phenyl Containing 1,2,3-Thiadiazole Derivatives via Ugi Reaction and Their Biological Activities显示文摘包含 4-methyl-1,2,3-thiadiazole 衍生物的一系列新奇 3,5-dichloro-4-(1,1,2,2-tetrafluoroethoxy ) 苯基经由 Ugi 反应被设计并且综合。他们的结构被红外, 1H NMR, 13C NMR 和高分辨率的集体光谱学证实。初步的生物鉴定结果显示一些标题混合物在 50 g/mL 举办了好杀真菌剂活动;大多数混合物在 500 g/mL 和 100 g/mL 对烟草马赛克病毒介绍了直接抑制活动,好 inactivation 和药品活动的某个度;一些混合物对 Plutella xylostella L 显示出好 larvicidal 活动。在对在 2 g/mL 的一种蚊虫 pipiens pallens 的 200 g/mL 和优秀 larvicidal 活动。 | Wang Shouxin Wang Huan Fan Zhijin Fu Yifeng Mi Na Zhang Jufang Zhang Zhengcai Belskaya Nataliya P. Bakulev Vasiliy A. | 2011 | Chinese Journal of Chemistry2011，29，2： | 4 |
| 8 | Airflow patterns upwind of obstacles and their significance for echo dune formation:A field measurement of the effects of the windward slope angle显示文摘The velocities in front of five topographic obstacles with windward slope angles between 45° and 80° were measured using ultrasonic anemometers in the field at the southeastern margin of the Tengger Desert.The characteristics of the horizontal and vertical velocities indicated that the airflow pattern was significantly influenced by the obstacle's windward slope angle.The horizontal flow decelerated but the vertical flow accelerated upwind of the obstacles when the windward slope was less than 60°,but a reversed flow formed in front of steeper obstacles.The size of the area occupied by the reversed horizontal component increased with increasing windward slope,but the region of reversed vertical velocity became narrower and taller.Airflow turbulence was strengthened as the wind approached the obstacle,and low-frequency high-energy velocity fluctuations were observed upwind of the obstacle,and could affect the entrainment and saltation processes of sand particles.Turbulence intensities for both the horizontal and vertical components of the airflow increased with increasing windward slope and with decreasing distance from the obstacle.The deceleration and downward movement of airflow upwind of the obstacle would result in supersaturation of the air-sand flow,leading to deposition of moving sand,and these deposited grains would become the material basis for the formation of echo dunes.The reversed airflow would both determine the initial position of the echo dune and provide the necessary motive power to subsequently shape the echo dune. | GuangQiang Qian ZhiBao Dong WanYin Luo ZhengCai Zhang AiGuo Zhao | 2012 | Science China Earth Sciences2012，55，4： | 3 |
| 9 | The trend of sand flux and the meteorology elements changes in the near-surface layer of Tengger desert in the spring of 2006显示文摘Dust storm events,especially those associated with strong winds,are immediately dangerous,and have long-term harmful effects.During a dust storm event,dust in the near-surface atmospheric layer decreases visibility,and changes local meteorological parameters.In this paper,we analyzed levels of near-surface turbulence during and outside a dust storm event and found differences in the degree of turbulence,with wind speed increasing and amounts of windblown sand greatly increasing air turbu-lence during the dust storms compared with the corresponding values on a sunny day.In addition,the wind profile during the dust storm deviated from the normal profile and became more complex.In the near-surface atmospheric layer,sand and dust flux during the dust storm also differed from those on a sunny day. | ZHANG ZhengCai DONG ZhiBao HAN LanYing ZHAO AiGuo | 2008 | Chinese Science Bulletin2008，53，21： | 2 |
| 10 | Geomorphology of star dunes in the southern Kumtagh Desert, China: control factors and formation显示文摘 | Zhibao Dong Zhengcai Zhang Guangqiang Qian Wanyin Luo Ping Lv Junfeng Lu | 2013 | Environmental Earth Sciences2013，，1： | 2 |
| 11 | Geomorphological hierarchies for complex mega-dunes and their implications for mega-dune evolution in the Badain Jaran Desert显示文摘 | Zhibao Dong Guangqiang Qian Wanyin Luo Zhengcai Zhang Shengchun Xiao Aiguo Zhao | 2008 | Geomorphology2008，，3： | 2 |
| 12 | Observations of Gobi aeolian transport and wind fetch effect显示文摘The wind fetch effect is important to wind erosion and aeolian transport and controls aeolian flux.It is useful to study the wind fetch effect in determining the aeolian transport mechanism and improving our knowledge of aeolian physics and wind erosion.In this paper,multichannel samplers measure aeolian transport at different heights above an artificial Gobi surface in the southeastern region of the Tengger Desert.The results show that aeolian transport flux can be expressed as an exponential function of height.Wind fetch obviously affects aeolian flux and aeolian transport.The coefficients and relative decay rate of aeolian flux decrease and then increase with increasing wind fetch distance.Aeolian transport depends on the height and fetch distance;aeolian transport increases and then decreases with increasing fetch distance,reaching a maximum at a fetch distance of about 34 m at the very near surface.The fetch distance of maximum aeolian transport tends to increase with height. | ZHANG ZhengCai DONG ZhiBao ZHAO AiGuo | 2012 | Science China Earth Sciences2012，55，8： | 2 |
| 13 | Visual Servo Stabilization of Nonholonomic Mobile Robot Based on Epipolar Geometry and 1D Trifocal Tensor显示文摘 | CAO Zhengcai YIN Longjie FU Yili ZHANG Jie | 2013 | Chinese Journal of Electronics2013，22，4： | 2 |
| 14 | The characteristics of aeolian sediment flux profiles in the south-eastern Tengger Deser显示文摘 | Zhang Zhengcai Dong Zhibao Zhao Aiguo | | Sedimentology0，58，： | 1 |
| 15 | An improved TS algorithm for loss-minimum reconfiguration in large-scale distribution systems显示文摘 | ZHANG Dong FU Zhengcai ZHANG Liuchun | 2007 | Electric Power Systems Research2007，77，56： | 1 |
| 16 | An improved TS algorithm for loss-minimum reconfiguration in large-scale distribution systems显示文摘 | Zhang Dong Fu Zhengcai Zhang Liuchun | 2007 | Electric Power Systems Research2007，77，： | 1 |
| 17 | Induced B7-H1 expression on human renal tubular epithelial cells by the sublytic terminal complement complex C5b-9显示文摘 | Yongwen Chen Jingbo Zhang Guoning Guo Zhihua Ruan Man Jiang Shengxi Wu Sheng Guo Lei Fei Yuyu Tang Chengying Yang Zhengcai Jia Yuzhang Wu | 2008 | Molecular Immunology2008，，3： | 1 |
| 18 | An improved TS algorithm for loss minimum reconfiguration in large scale distribution systems 显示文摘 | ZHANG Dong FU Zhengcai ZHANG Liuchun | 2007 | Electric Power Systems Research2007，77，56： | 1 |
| 19 | The effect of re-stored microbiotic crusts on erosion of soil from a desert area in Chi-na显示文摘 | Zhang Zhengcai Dong Zhibao Zhao Aiguo | 2008 | Journal of Arid Environments2008，72，5： | 1 |
| 20 | Analysis of the wind regime in context of dune geomorphology for the Kumtagh Desert, Northwest China显示文摘 | Zhibao Dong Zhengcai Zhang Ping Lv Guangqiang Qian Wanyin Luo | 2012 | Zeitschrift für Geomorphologie NF2012，，4： | 1 |
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