柴油机燃烧室径深比对性能的影响研究

针对某增压中冷六缸柴油机,模拟计算了3种不同径深比燃烧室在额定工况下的燃烧过程和性能,3种径深比分别为3.8、4.45和5.2.模拟研究表明:径深比对柴油机性能的影响较大.随着径深比的增大,柴油机燃烧室内油气混合更充分,使得燃烧温度增大,平均指示压力、升功率、扭矩等动力性指标增加,经济性指标比油耗有所下降;同时因高温燃烧生成的Soot和NO的排放量增多.

不同入路显微手术治疗基底节区高血压脑出血的效果对比

目的探讨不同入路显微手术治疗基底节区高血压脑出血的效果。方法将我院2017年1月—2021年3月期间98例患者分组,按照随机数字表法分为对照组49例,给予颞叶皮层入路显微手术治疗,观察组49例给予经外侧裂入路显微手术治疗,观察2组预后状态、术后情况、日常生活能力及并发症发生情况。结果术后半年,观察组预后状况优良率(81.63%)高于对照组(59.18%,P<0.05);观察组血肿消除率(95.92%)大于对照组(81.63%,P<0.05),2组手术时间[观察组(141.22±20.15)min,对照组(134.49±22.58)min]对比差异无统计学意义(P>0.05);观察组日常生活能力优于对照组(P<0.05);观察组并发症(14.28%)与对照组对比无统计学意义(10.20%,P>0.05)。结论相较于颞叶皮层入路,外侧裂入路下显微手术治疗基底节区高血压脑出血患者对血肿清除效果更佳,以此提高手术预后及生活能力,不会增加手术时间及术后并发症发生情况。

Spatial Distribution Characteristics of Forest Parks in Shandong Province

The spatial distribution characteristics of forest parks in Shandong Province were studied using geographical concentration index,Gini coefficient,and ArcGIS analysis software.The results show that the forest parks in Shandong Province are concentrated in the province and in the five subregions,and the equilibrium degree of the distribution is low.The density of forest parks in Shandong Province is high in eastern Shandong and central Shandong but low in western Shandong.The number of forest parks in the eastern coastal areas of Shandong Province is larger than the number of forest parks in the inland areas of Shandong Province.