Results 11 to 20 of about 738,729 (152)
, 1997 降低风洞气流总温是提高亚，跨声速风洞雷诺数的有效方法，现有采用液氮致冷的生产型低温风洞能满足设计各种新型飞机进行气动试验所需的雷诺数要求，但由于需耗用大量液氮，导致运行费用高昂，此外，排出大量低温缺氧气体还严重影响生态和环境 ...
俞鸿儒
core +2 more sources
, 2002 对涡轮流量传感器进行了理论分析,给出了涡轮流量计仪表常数的计算方法,讨论了获得较大固有仪表常数K_0时涡轮传感器结构参数（如叶片数、涡轮半径、口径等）的优化组合问题,通过多相流动实验,总结出K_0与流动密度之间的实验关系,由此给出用涡轮流量计测量多相流的半理论半经验公式,并在油井多相流量测量中得到了实际应用,符合较好。对涡轮流量传感器进行了理论分析,给出了涡轮流量计仪表常数的计算方法,讨论了获得较大固有仪表常数K_0时涡轮传感器结构参数（如叶片数、涡轮半径、口径等）的优化组合问题,通过多相流动实验 ...
田树祥 +4 more
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, 2003 由厦门大学财政系提供的2003年国有资产监管体制与公共财政制度改革国际会议论文集06本报告以经营性国有资产为研究对象，对人们普遍关注的国有资产流失问题进行了系统分析。首先从现象入手，将社会经济生活中典型性的国有资产流失归纳为五种表现形式:合资过程中的国有资产流失、股份制改造过程中的国有资产流失、企业内部控制薄弱形成的流失、承包体制下造成的流失以及决策失误造成的流失。然后，从国有企业所有者缺位、人事制度缺失、监督机构和法制不健全、经营者诚信度下降等方面深入分析了国有资产流失的根源。最后 ...
《防治国有资产流失问题研究》课题组
core
Shuitu Baochi Xuebao, 2023 为探究不同前期土壤含水量条件下坡面产流产沙特征及产流产沙关系,以安塞黄绵土为研究对象,通过设置6个前期土壤含水量处理(5%,10%,15%,20%,25%,30%),采用室内人工模拟降雨试验来系统研究前期土壤含水量对坡面产流产沙过程的影响。每个含水量处理设置2个重复,坡面坡度为15°,设计雨强为90 mm/h,降雨历时为1 h。结果表明:(1)随着前期土壤含水量的升高,坡面初始产流时间幂函数减小,产流量线性增大。(2)坡面土壤流失量随前期土壤含水量增大呈幂函数增加,高含水量组(29.3 ...
淡彩虹 +5 more
doaj
Ultrasonic Vibration Assisted Laser Processing: A Hybrid Paradigm for Extreme Surface Enhancement
Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT Traditional laser processing techniques offer many advantages, but they often encounter limitations such as heat‐affected zones, recast layers, residual tensile stresses, and poor surface finish. The integration of ultrasonic vibration (UV) presents a promising hybrid approach to overcome these challenges by introducing beneficial effects like
Aziz Ul Hassan Mohsan +6 more
wiley +1 more source
Shuitu Baochi Xuebao, 2017 为研究降雨因子对粉煤灰产流产沙的影响，揭示粉煤灰产流产渣的规律，采用径流小区定位观测试验，研究雨季期粉煤灰径流小区在自然降雨条件下的产流产渣特征。结果表明：（1）观测期内总降雨量为1 160.0 mm，侵蚀降雨量为720.7 mm，7月份降雨、侵蚀降雨均为最多，分别为409.6 mm和217.1 mm，暴雨的侵蚀降雨量最大，为280.1 mm；（2）7月份产流产渣最多，3个小区的产流产渣量分别为0.72，1.06，0.67 m3和0.30，0.90，0.21 kg，暴雨的产流产渣量最大，分别为0.62 ...
张华明 +7 more
doaj
Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT Photocatalytic hydrogen peroxide (H2O2) production from water and oxygen driven by solar energy represents a highly promising green and sustainable strategy. Herein, lignin‐derived carbon quantum dots (LCDs) were strategically introduced at the heterojunction between a Bi‐based metal organic framework (Bi‐MOF) and ZnIn2S4 (ZIS).
Wanpeng Sun +8 more
wiley +1 more source
Shuitu Baochi Xuebao, 2020 为定量研究小麦秸秆覆盖对坡面产沙产流过程及减水减沙效益的影响，采用室内人工模拟降雨试验，研究在降雨强度为90 mm/h时，不同秸秆长度和秸秆覆盖量下的坡面产流产沙特征和产流产沙过程规律，结果表明：（1）在相同秸秆长度下，随秸秆覆盖量增加，产流量产沙量极显著减少 ...
曾建辉 +5 more
doaj
Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT Microstructural characterization of Li0.32La0.56Fe0.01Ti0.94Sb0.06O3 (LLFeTSO) using AC‐TEM revealed that Fe3+/Sb3+ ion co‐doping induces the migration of lattice oxygen to grain boundaries (GBs), enhancing GB conductivity. However, the atomic arrangement at the GBs remains highly ordered and lacks sufficient cation vacancy carriers.
Binxuan Jiang +8 more
wiley +1 more source
Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT NiCoCrAlYTa coatings are widely used as bond coats in thermal barrier coating (TBC) systems for gas turbines and aeroengines to provide oxidation resistance and support the formation of a protective thermally grown oxide (TGO). Herein, high‐current pulsed electron beam (HCPEB) modification was utilized to strengthen a NiCoCrAlYTa coating by ...
Xiangcheng Li +6 more
wiley +1 more source