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目的为探究阻沙固沙带不同治沙措施对土壤理化性质和酶活性的影响及其相关关系,为措施选择及效益评价提供技术支撑。方法以流动沙丘+梭梭(CK)为对照组,以生态垫沙障+梭梭(ES)、尼龙网格沙障+梭梭(NS)、编织袋沙障+梭梭(WS)、草方格沙障+梭梭(GS)、黏土沙障+梭梭(CS)为试验组,对6种不同治沙措施0~60 cm土层土壤的理化性质和酶活性进行分析。结果相较于CK治沙措施,其他5种治沙措施土壤理化性质和酶活性均存在显著变化。1)在0~60 cm土层土壤的pH变化不显著,土壤水分体积分数(SWC ...
田永胜, 马瑞, 刘腾, 马彦军
doaj
雷击杆塔时会导致不满足国标要求的临近埋地油气管道产生过高电位升,如何在空间受限情况下进行改造成为了亟待解决的问题。提出基于杆塔接地装置布置的管道电位抑制方法,通过CDEGS建立临近接地装置的埋地油气管道模型,开展模拟试验验证其准确性,定义风险系数评估管道风险并分析隔离、垂直引流和水平引流3类措施对管道电位升的抑制效果。结果表明:加装隔离墙降压效果最优,最高可降38.2%;引流类措施在高土壤电阻率情况下降压效果更好,选用30 m左右的接地体效益最高,最后提出了一种组合措施,可以使风险系数降低到安全区附近 ...
双明镜 +6 more
doaj
文中提出交流电桥对地分布阻抗影响测量误差的分析,和降低QS1型电桥测量误差的措施,尤其对测量小电容试品thδ出现负值(及低值)问题的分析,可提供目前高压测试中某些线索,以减少对试品绝缘的误判断。
张国明
doaj
本文对电容式电压互感器的空载误差和负载误差特性进行了研究 ,提出了保证CVT空载误差特性时其变压器的额定磁通密度 (BN)。通过改变CVT中压变压器绕组的布置方式 ,可降低其直流电阻 ,从而改善负载误差特性 ...
王德忠, 王季梅
doaj
[Rehabilitation guidelines and specifications for traumatic spinal cord injury (2025 edition)]. [PDF]
Professional Committee Of Spine And Spinal Cord Injury Rehabilitation China Association Of Rehabilitation Of Disabled Persons +3 more
europepmc +1 more source
[Medical treatment standards for emergency burn wounded (2025 edition)]. [PDF]
National Health Commission Of The People's Republic Of China.
europepmc +1 more source
[Medical treatment standards for emergency trauma wounded (2025 edition)]. [PDF]
National Health Commission Of The People's Republic Of China.
europepmc +1 more source
[A review of research progress in integrated traditional Chinese and Western Medicine for liver diseases]. [PDF]
Zhang Q +6 more
europepmc +1 more source
[Analysis and Projection of the Burden of Chronic Respiratory Diseases Attributable to Smoking in China, 1990-2021]. [PDF]
Xie X +6 more
europepmc +1 more source

