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Evaluating the impact and significance of meteorological factors upon dust storm occurrence

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Research in Cold and Arid Regions 2011年第2期3卷 161-171页

作者： WanYuan Li ShiHua Lv Ye Yu ZhiBao Dong ZhiBao Shen yuchun chen Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou Gansu 730000 China. Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou Gansu 730000 China.

In this article, the quantitative impact and significance of factors on dust storm occurrence have been analyzed in detail, based on spring daily data sets of 17 meteorological factors and dust storm records during the period of 1954-2005 for 60 gauge stations distributed over Gansu Province of China. Results show that daily mean and maximum wind speeds and evaporation have a positive effect on dust storm occurrence, i.e., their increase can result in an increase of dust storm occurrence. Inversely, daily mean and minimum relative humidity, lowest surface air pressure, vapor pressure and number of sunny hours have a negative effect on dust storm occurrence. However, daily mean and highest surface air pressure; mean, highest and lowest surface air temperature; and precipitation of 20：00-08：00, 08：00-20：00 and 20：00-20：00 have a positive effect on dust storm occurrence in some places but negative in other places. On average, daily maximum and mean wind speeds, direction of the maximum wind, number of sunny hours and evaporation have a significant effect on dust storm occurrence in Gansu Province, but precipitation of 20：00--08：00, 08：00-20：00 and 20：00-20：00, and mean surface air pressure and temperature all have a minor influence upon dust storm occurrence.

关键词： Gansu Province meteorological factor spring dust storm occurrence impact and significance

Effects of biofertilizer and water-saving irrigation interactions on the leaf photosynthesis and plant growth of tomatoes

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 177-185页

作者： Danyan chen yuchun Ai Peizhe Li Yue Dong Hailing Li Changyi Wang Xiaorui Jiang Shilong Li Yan Shen Aijun Dai Yuanyuan Feng College of Horticulture Jinling Institute of TechnologyNanjing 210038China Co-Innovation Center for Sustainable Forestry in Southern China College of Forestry and GrasslandCollege of Soil and Water ConservationNanjing Forestry UniversityNanjing 210037China Institute of Agricultural Resources and Environment Jiangsu Academy of Agricultural SciencesNanjing 210014China Agriculture Exchange and Cooperation Center of Shandong Province Jinan 250100China Murdoch Applied Innovation Nanotechnology Research Group College of ScienceHealthEngineering and EducationMurdoch UniversityPerthWA 5150Australia

Irrigation and fertilizer interaction is an efficient cultivation management strategy for facility ***,the effects of irrigation and fertilizer management on tomato growth and its physiological factors remain *** this study,two irrigation patterns(W1,conventional irrigation;W2,water-saving irrigation)and four fertilizer application patterns(CF,chemical fertilizer;BOF,biological organic fertilizer;NPK,nutrient compound fertilizer;BOF+NPK)were selected to observe the effects of their interaction on cherry tomato plant growth,leaf photosynthesis and fruit quality through pot *** results showed that W2 treatments promoted plant height growth compared to W1 under the same fertilizer ***,irrigation and fertilizer management had significant effects on net photosynthetic rate,intercellular oxidation concentration,stomatal conductance and transpiration rate at the first sequence flowering and fruiting *** maximum tomato plant height(99.0 cm)was achieved under the irrigation and fertilizer pattern of BOF and W2,along with the highest fruit yield of 1.98 kg/plant,which was approximately 31.1%higher than the minimum yield under the combined CF and W2 *** W2 treatments,the application of either NPK or BOF increased the soluble sugar content of *** structural equation models showed that the soil alkali hydrolyzed nitrogen could directly significantly affect the yield and soluble *** findings suggest that optimization of irrigation-fertilizer interactions positively regulates tomato growth,providing an efficient model for tomato irrigation and fertilizer management and a reference for sustainable development of facility agriculture.

关键词： irrigation-fertilization interaction cherry tomato plant height leaf photosynthesis fruit yield and quality

The South China Sea thermohaline structure and circulation

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Acta Oceanologica Sinica 2002年第2期21卷 227-261页

作者： Peter C. Chu, Binbing Ma, yuchun chen1. Naval Postgraduate School, Monterey, California, USA2. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences, Lanzhou, China Naval Postgraduate School

In this study, we used the Navy' s Master Oceanographic Observation Data Set(MOODS), consisting of 116019 temperature and 9617 salinity profiles, during 1968-1984 to investigate the temporal and spatial variabilities of South China Sea thermohaline structures and circulation. For temperature, profiles were binned into 204 monthly data sets from 1968 to 1984 (17 years). For salinity, profiles were binned into 12 climatological monthly data sets due to the data paucity. A two-scale optimal interpolation method was used to establish a three-dimensional monthly-varying gridded data set from MOODS, covering the area of 5°-25°N and 105° - 125°E and the depth from the surface to 400 m. After the gridded data set had been established, both composite analysis and the Empirical Orthogonal Function (EOF) analysis (for temperature only) were used to identify the major thermohaline fratures including annual mean, monthly anomalies, and interannual thermal variabilities. The inverted monthly circulation pattern using the P - vector method is also discussed.

关键词： The South China Sea thermohaline structure circulation

优质均衡视角下乡村小规模学校教育质量困境与对策

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华中师范大学学报（人文社会科学版） 2019年第2期58卷 157-167页

作者：赵丹陈遇春赵阔西北农林科技大学人文社会发展学院农村社会研究中心陕西杨凌712100

在"优质均衡"成为义务教育发展重点任务的新时期,乡村小规模学校是确保偏远地区儿童公平接受优质教育、助力乡村教育振兴的重要载体。但现实中,小规模学校在教育输入质量、教育过程质量和教育结果质量等方面均面临突出困境。其深层次原... 详细信息

在"优质均衡"成为义务教育发展重点任务的新时期,乡村小规模学校是确保偏远地区儿童公平接受优质教育、助力乡村教育振兴的重要载体。但现实中,小规模学校在教育输入质量、教育过程质量和教育结果质量等方面均面临突出困境。其深层次原因在于:城乡二元结构导致小规模学校弱势地位难改变、现行教育财政管理体制不尽合理、教师资源配置政策偏离学校实际、办学优势挖掘不足以及学校—社区互动机制尚未建立。因此,各级政府应从提升办学地位、强化省级政府财政责任、加强师资配置、变革课程教学模式、促进学校-社区互动等方面加强小规模学校建设,弥补乡村教育短板,促进教育优质均衡发展。

关键词：乡村小规模学校教育质量义务教育优质均衡城乡教育公平

基于层流流量计的航发燃油流量动态测量技术研究

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仪器仪表学报 2021年第3期42卷 35-41页

作者：王筱庐陈玉春蒋宇翔西北工业大学动力与能源学院西安710072

为解决航空发动机过渡态燃油测量问题,研究了基于层流流量计(LFM)的航空燃油流量动态测量技术。设计了一款量程为0~3 000 mL/min的液体LFM,在小型涡轮喷气式发动机试车台上对其进行了试验,并与科里奥利流量计(CMF)进行了比对,试验结果显... 详细信息

为解决航空发动机过渡态燃油测量问题,研究了基于层流流量计(LFM)的航空燃油流量动态测量技术。设计了一款量程为0~3 000 mL/min的液体LFM,在小型涡轮喷气式发动机试车台上对其进行了试验,并与科里奥利流量计(CMF)进行了比对,试验结果显示LFM具有优秀的动态特性。当发动机处于稳态时,LFM测量结果与CMF吻合较好,相对误差为-1.25%~1.16%,与LFM校准时-1.24%~1.26%的相对误差相吻合。当发动机处于过渡态时,LFM能很好地跟随泵后油压,而CMF则无法跟随泵后油压,存在大约2 s的滞后。LFM的测量结果能与发动机起动、加/减速时的控制逻辑保持一致。本文研究可为航空发动机试车技术的研究和LFM应用的拓展提供有价值的参考。

关键词：层流流量计航空发动机燃油过渡态动态测量

A descriptor for the local dust storm occurrence probability constituted by meteorological factors

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Research in Cold and Arid Regions 2012年第2期4卷 140-153页

作者： WanYuan Li ShiHua Lu ZhiBao Dong ShiGong Wang ZhiBao Shen yuchun chen Ye Yu YinHuan Ao Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou Gansu 730000 China Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou Gansu 730000 China Key Laboratory for Semi-Arid Climate Change of the Ministry of Education Lanzhou University Lanzhou Gansu 730000 China

Based on daily data sets of 17 meteorological factors during the period of 1954-2005 for 60 gauge stations distributed over Gansu Province of China and the corresponding dust storm records, the dust storm probabilities related to different classes of each factor have been calculated and analyzed. On the basis of statistical analysis, a meteorological descriptor quantifying the daily dust storm occurrence probability for each station, which is referred to as the Dust Storm Occurrence Probability Index （DSOPI）, has been effectively established. According to the statistical characteristics of DSOPI for each station, a feasible judging criterion for a dust storm event has been determined, which can greatly contribute to forecasting dust storms and completing the unavailable historic dust storm records. Meanwhile, the average daily dust storm probability related to each factor on the dust storm day for each station has been specially analyzed in detail, finally disclosing that, in general, the more signifi- cant one factor＇s influence on dust storms, the greater its contribution to them; and each factor＇s contribution clearly varies from place to place. Moreover, on average, maximum and mean wind speeds, maximum-speed wind direction, daily sunny hours, evaporation, mean and lowest relative humidity, lowest surface air pressure and vapor pressure contribute to dust storm events in Gansu Province most greatly in order among all the 17 involved factors.

关键词： meteorological factor dust storm occurrence significance probability index contribution

ISOLATION AND CHARACTERIZATION OF BACTERIA FOR REMOVAL OF SULFUR IN ORGANIC COMPOUNDS

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化工学报 2000年第S1期51卷 272-275页

作者： Jiang chengying, Xie yuchun, Liu Huizhou and chen Jiayong (Young Scientist Laboratory of Separation Science & Engineering, State Key Laboratory of Biochemical Engineering, Institute of Chemical Metallurgy, Chinese Academy of Sciences, Beijing 100080,)

Four bacterial strains have been isolated for their ability to growth on dibenzothiophene (DBT), dibenzothiophene sulfone (DBTO2). The results show that different bacteria strains oxidize the DBT to different products through different pathways. R-6 and R-16 metabolize DBT to DBTO2 and HBP; they are identified as species of Bacillus brevis and Bacillus sphaericus. For long time storage, R-9 identified as Nocardia globerula oxidizes DBT to DBT-sulfone (DBTO2) and benzenamine n-phenyl. The optimum temperature and pH for growth of R-16 are 32℃ and 7.02 respectively. The pH of broth decreases during the processes.

关键词： biodegradation biodesulfurization dibenzothiophene

Fluxes of CO_2, N_2O and CH_4 from a typical temperate grassland in Inner Mongolia and its daily variation

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Chinese Science Bulletin 2000年第17期45卷 1590-1594页

作者： DONG Yunshe, ZHANG Shen, Ql yuchun, chen Zuozhong & GENG Yuanbo1. Institute of Geography, Chinese Academy of Sciences, Beijing 100101, China:2, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China Correspondence should be addressed to Dong Yunshe Institute of Geography Chinese Academy of Sciences Beijing China Institute of Botany Chinese Academy of Sciences Beijing China

Using a dark enclosed chamber technique, the fluxes of CO2, N2O and CH4 from nature and disturbed grassland were measured on the spot in Inner Mongolian Temperate Grassland along the annual rainfall gradient section ranging from 450 to 200 mm. The results showed that the measured mean fluxes of CO2, N2O and CH4were (1 180.4 ±308.7), (0.010 ± 0.004) and (-0.039 ± 0.016) mg · m-2/h, respectively. The decrease of the fluxes of CO2, N2O and CH4 follows with that of annual rainfall gradient in the measurement area. Human activities, such as grazing and reclamation are also critical factors to affect the fluxes of these gases from grassland. Daily continuous measurement of CO2, N2O and CH4 fluxes showed a strong diurnal variation with higher emission in the daytime. A good relationship between the fluxes of CO2, N2O, CH4 and temperature was exposed in this study.

关键词： Northeast China Transect (NECT) temperate grassland greenhouse gas flux.

我国农科拔尖创新人才培养模式构建研究——基于西北农林科技大学的实践探索

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中国高教研究 2011年第6期 62-64页

作者：陈遇春王国栋西北农林科技大学创新实验学院

培养创新型人才已经成为当前高等学校的战略使命。在建设创新型国家的时代背景和国际人才竞争的大格局下,高水平研究型农业大学应该积极适应我国农业现代化发展需要,肩负起培养和造就具有农林学科特色的拔尖创新人才的重任。西北农林科... 详细信息

培养创新型人才已经成为当前高等学校的战略使命。在建设创新型国家的时代背景和国际人才竞争的大格局下,高水平研究型农业大学应该积极适应我国农业现代化发展需要,肩负起培养和造就具有农林学科特色的拔尖创新人才的重任。西北农林科技大学在建设世界一流农业大学进程中,主动顺应高等教育改革趋势和农业科技发展要求,积极探索农科拔尖创新人才培养模式和途径,建设教学团队,创体体制机制,培育创新文化,取得了良好成效。

关键词：培养模式改革教学约定团队建设制度创新