黄土高原地区气候变化及其对冬小麦生产潜力的影响

气候变化对冬小麦生长发育的影响一直是热点问题。为了探讨黄土高原地区气候变化对冬小麦生产潜力的影响,以甘肃省9个冬小麦种植区为研究区,利用农业气象观测站1961—2017年逐日气象资料和冬小麦农业气象观测资料,运用线性倾向估计方法分析了近57 a黄土高原地区气候变化特征;利用农业生态区法AEZ模型计算9个站点1961—2017年57 a冬小麦光温生产潜力和气候生产潜力,研究近57 a黄土高原地区冬小麦光温生产潜力和气候生产潜力的变化趋势,分析影响冬小麦光温生产潜力和气候生产潜力变化的主要气象因素。结果表明,(1)近57 a,黄土高原地区气温表现为显著升高趋势,而降水量和太阳辐射则表现为减少趋势。(2)冬小麦生育期内气温和≥10℃积温均表现为升高趋势,气候倾向率为0.29℃·(10 a)^(−1)(P<0.01);降水量呈增加趋势,但太阳辐射呈减少趋势。(3)伴随气温的升高和≥10℃积温的增加,冬小麦光温生产潜力和气候生产潜力均表现为增加趋势,气候倾向率分别为663.05 kg·hm^(−2)·(10 a)^(−1)和517.57 kg·hm^(−2)·(10 a)^(−1)。冬小麦生产潜力主要受气温的影响,气温的升高是黄土高原地区冬小麦生产潜力增加的主要原因。黄土高原地区冬小麦生育期内气温和≥10℃积温的升高,有利于冬小麦光合作用,是冬小麦光温生产潜力和气候生产潜力提高的主要因素。该研究可为气候变化背景下黄土高原半干旱区冬小麦应对气候变化提供理论依据。

Application of Integration of Spatial Statistical Analysis with GIS to Regional Economic Analysis

This paper summarizes a few spatial statistical analysis methods for to measuring spatial autocorrelation and spatial association, discusses the criteria for the identification of spatial association by the use of global Moran Coefficient, Local Moran and Local Geary. Furthermore, a user-friendly statistical module, combining spatial statistical analysis methods with GIS visual techniques, is developed in Arcview using Avenue. An example is also given to show the usefulness of this module in identifying and quantifying the underlying spatial association patterns between economic units.

Study On the Tribological Behavior of the Arc-added Glow Discharge Plasma Non-hydrogen Carburization On Titanium Alloy Surfaces

This paper introduces a new titanium alloys surface strengthening treatment by using the arc-added glow discharge plasmas non-hydrogen Carburization technique. High purity and high strength graphite is selected as cooling cathode arc source for supplying carbon atoms and particle, which migrate to the titanium alloy(Ti6A14V) surface and form modified layer. Thus, the hydrogen embrittlement is avoided while the tribological behavior of the titanium alloy surface is improved in the respects of anti-friction and anti-wear ability.The tribological behavior of the modified layer under dry sliding against SAE52100 steel was evaluated on a ball-on-disc test rig. The results showed that the modified layer obtained a thickness of 30u,m at 980°C, 30minutes. The microhardness of the Ti6A14V alloy surface attained 936 HV, which was much larger than that of the T16A14V alloy. The TJ6A14V alloy was characterized by adhesion wear and scuffing under dry sliding against the steel, while the surface modified layer experienced much abated adhesion wear and scuffing under the same testing condition. This could be attributed to the carbon element with different modalities exists in the modified layer. The modified layer showed good friction-reducing and fair anti-wear ability in dry sliding against the steel. Using the SEM, XRD and XPS, the phase structure and morphology of the Carburization modified layer was analyzed.

基于Aspen Plus的矿渣立磨粉磨工艺模拟

利用Aspen Plus模拟软件建立矿渣立磨粉磨工艺流程稳态模型,通过对比模拟结果和实际数据,验证了工艺模型的可靠性。同时利用软件的灵敏度和优化分析工具研究了循环风量和矿渣水分对矿渣立磨粉磨工艺系统的影响。

专业型医学硕士研究生规范化培训期间职业态度变化归因分析--基于15例郑州市高校在读硕士访谈资料的质性研究

目的:探讨专业型医学硕士在规范化培训期间的职业态度现状及影响其态度变化的因素。方法:基于15份访谈资料,依据扎根理论方法,通过NVivo 11软件对资料进行整理,对专业型医学硕士的职业态度转变进行质性归因分析。结果:在规范化培训中,专业型医学硕士面临来自领导因素、外部因素及内部因素的共同影响,其中,管培机制建设不足、工作压力与经济支持不均衡、医患关系紧张及不良舆论、家庭内部与自我认知不符是导致其职业态度转变的主要因素。结论:完善专业型医学硕士的规范化培训方案,加强针对专业型医学硕士培养的投入力度,严格治理恶意伤医事件,改善医疗职业环境,加强专业型医学硕士在规范化培训期间的职业素养与精神教育。