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基于颗粒阻尼的变频空调压缩机管路减振设计

中国机械工程 2022年第18期33卷 2172-2182,2189页

作者：张鸿权肖望强厦门大学航空航天学院厦门361102

为解决变频空调压缩机管路振动问题,利用有限元法对管路进行动力学分析,在测点位置进行35~72 Hz变频试验测试。建立管路颗粒阻尼的能耗模型,通过离散元法确定颗粒材质、粒径和填充率等最优设计参数,并搭建管路减振试验台。振动试验结果... 详细信息

为解决变频空调压缩机管路振动问题,利用有限元法对管路进行动力学分析,在测点位置进行35~72 Hz变频试验测试。建立管路颗粒阻尼的能耗模型,通过离散元法确定颗粒材质、粒径和填充率等最优设计参数,并搭建管路减振试验台。振动试验结果表明:采用颗粒材质为铁基合金、颗粒粒径为2 mm、阻尼器填充率为90%的设计参数,当进气管采用B型阻尼器和45°布置方式,3个测点位置的加速度最大减幅分别为36.57%,30.15%,45.79%,当排气管采用A型阻尼器和水平方式时,3个测点位置的加速度最大减幅分别为40.87%,62.04%,50.42%。最后将试验的加速度响应变化趋势与耗能模型分析结果进行对比,验证了管路颗粒阻尼耗能模型的可行性。

关键词：压缩机管路颗粒阻尼能耗模型设计参数布置方式

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用于苯选择加氢制环己烯的非晶态合金Ru-La-B/ZrO_2催化剂的失活与再生

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催化学报 2005年第5期26卷 407-411页

作者：王辉刘仲毅师瑞娟张永娜张洪权刘寿长郑州大学化学系河南郑州450052

研究了在中试装置上经长期运转后的非晶态合金Ru La B/ZrO2 催化剂的失活原因与再生方法.结果表明:催化剂失活不是由微孔堵塞、比表面积减小、晶粒长大或催化剂中毒而引起的,而是由于在长期运转过程中催化剂吸附了反应浆液中的Zn2 +和... 详细信息

研究了在中试装置上经长期运转后的非晶态合金Ru La B/ZrO2 催化剂的失活原因与再生方法.结果表明:催化剂失活不是由微孔堵塞、比表面积减小、晶粒长大或催化剂中毒而引起的,而是由于在长期运转过程中催化剂吸附了反应浆液中的Zn2 +和反应器壁引入的Fe2 +,通过酸洗的方法可以使催化剂的活性和选择性基本恢复.

关键词：钌镧二氧化锆非晶态合金苯选择加氢环己烯失活再生

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浅谈石油企业技术创新

石油钻探技术 1999年第6期27卷 45-46页

作者：张洪泉毛国忠张向东胜利石油管理局黄河钻井总公司山东东营257064

详细论述了技术创新对石油企业发展的重要作用，指出了石油企业开展技术创新的途径及应注意的问题。

关键词：石油企业技术创新企业

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气相色谱法检测大孔吸附树脂中的有机残留物

色谱 2005年第6期23卷 655-658页

作者：贾存勤李阳春屠鹏飞张洪全北京大学药学院北京100083 甘肃农业大学草业学院甘肃兰州730050

建立了同时检测大孔吸附树脂中苯、甲苯、二甲苯、苯乙烯、二乙苯、二乙烯苯、萘、癸烷、十一烷和十二烷等10种有机残留物的测定方法.以二氯甲烷为提取溶剂,采用超声提取法对样品进行前处理.采用气相色谱法检测,色谱柱为DB-624毛细管柱... 详细信息

建立了同时检测大孔吸附树脂中苯、甲苯、二甲苯、苯乙烯、二乙苯、二乙烯苯、萘、癸烷、十一烷和十二烷等10种有机残留物的测定方法.以二氯甲烷为提取溶剂,采用超声提取法对样品进行前处理.采用气相色谱法检测,色谱柱为DB-624毛细管柱,检测器为氢火焰离子化检测器.上述10种有机残留物在12 min内能很好地分离,样品的加标回收率(n=3)为73.8%～107.9%,相对标准偏差为1.3%～4.4%,最低检测限为0.007～0.03 mg/L.本方法具有灵敏、准确、快速等特点.对9种商品树脂及其预处理品的有机残留物进行了测定,结果表明树脂预处理前后有机残留物的含量相差很大,经过预处理的树脂可以安全地应用于中药的生产.

关键词：气相色谱法苯甲苯二乙苯萘癸烷有机残留物大孔吸附树脂

Diatomic Pd catalyst with conjugated backbone for synergistic electrochemical CO_(2)reduction

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Nano Research 2024年第6期17卷 4850-4855页

作者： Wenxuan zhang Mengran zhang Hongjuan Wang Wen zhang Min zhang MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion School of Chemistry and Chemical EngineeringTianjin University of TechnologyTianjin 300384China

Double-site catalysts have attracted widespread attention in the field of electrocatalysis due to their high metal loading,adjustable active centres,and electronic valence ***,the development of bimetallic sites catalysts that coordinate with definite atoms is still in the exploratory ***,we designed and synthesized a bimetallic palladium complex(BPB-Pd_(2))with conjugated *** supported BPB-Pd_(2)was applied to electrochemical CO_(2)reduction reaction(CO_(2)RR)for the first *** as-obtained BPB-Pd_(2)gives an exceptional Faradaic efficiency of CO(FECO)of 94.4%at−0.80 V *** hydrogen electrode(RHE),which is significantly superior to monoatomic palladium catalyst(BPB-Pd1).The density functional theory(DFT)calculations revealed that the essential reason for the outstanding activity of BPB-Pd_(2)toward CO_(2)RR was that the electronic effect between diatomic palladium reduces the free energy change for CO_(2)RR ***,BPB-Pd_(2)exhibits moderate free energy change to form COOH*intermediate,which was beneficial for the generation of CO in CO_(2)RR.

关键词： synthesis electrocatalysis CO_(2)reduction bimetallic palladium complex synergistic catalysis

N-doped graphene quantum dot-decorated N-TiO2/P-doped porous hollow g-C_(3)N_(4) nanotube composite photocatalysts for antibiotic photodegradation and H2 production

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 165-178页

作者： Jingshu Yuan Yao zhang Xiaoyan zhang Junjie zhang Shen’gen zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Xi’an Fanyi University Xi’an 710105China Shunde Graduate School of University of Science and Technology Beijing Foshan 528399China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao SAR 820000China

Exclusive responsiveness to ultraviolet light (~3.2 eV) and high photogenerated charge recombination rate are the two primary drawbacks of pure TiO_(2). We combined N-doped graphene quantum dots (N-GQDs), morphology regulation, and heterojunction construction strategies to synthesize N-GQD/N-doped TiO_(2)/P-doped porous hollow g-C_(3)N_(4) nanotube (PCN) composite photocatalysts (denoted as G-TPCN). The optimal sample (G-TPCN doped with 0.1wt% N-GQD, denoted as 0.1% G-TPCN) exhibits significantly enhanced photoabsorption, which is attributed to the change in bandgap caused by elemental doping (P and N), the improved light-harvesting resulting from the tube structure, and the upconversion effect of N-GQDs. In addition, the internal charge separation and transfer capability of0.1% G-TPCN are dramatically boosted, and its carrier concentration is 3.7, 2.3, and 1.9 times that of N-TiO_(2), PCN, and N-TiO_(2)/PCN(TPCN-1), respectively. This phenomenon is attributed to the formation of Z-scheme heterojunction between N-TiO_(2) and PCNs, the excellent electron conduction ability of N-GQDs, and the short transfer distance caused by the porous nanotube structure. Compared with those of N-TiO_(2), PCNs, and TPCN-1, the H2 production activity of 0.1%G-TPCN under visible light is enhanced by 12.4, 2.3, and 1.4times, respectively, and its ciprofloxacin (CIP) degradation rate is increased by 7.9, 5.7, and 2.9 times, respectively. The optimized performance benefits from excellent photoresponsiveness and improved carrier separation and migration efficiencies. Finally, the photocatalytic mechanism of 0.1% G-TPCN and five possible degradation pathways of CIP are proposed. This study clarifies the mechanism of multiple modification strategies to synergistically improve the photocatalytic performance of 0.1% G-TPCN and provides a potential strategy for rationally designing novel photocatalysts for environmental remediation and solar energy conversion.

关键词： N-doped TiO_(2) N-doped graphene quantum dots P-doped g-C_(3)N_(4) porous hollow nanotube heterojunction photocatalysis

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大斜度大位移井岩屑床的解决方法

石油钻探技术 1999年第3期27卷 6-8页

作者：张洪泉任中启董明健胜利油田黄河钻井公司胜利油田钻井三公司

在大斜度大位移高难度定向井中，岩屑易在井眼中形成岩屑床，导致蹩泵、蹩钻甚至卡钻。本文在分析岩屑床的形成及危害的基础上，对岩屑床的清除办法进行了探讨，提出了将提高泥浆返速、改善泥浆性能与机械清除岩屑相结合的方法。胜利油... 详细信息

在大斜度大位移高难度定向井中，岩屑易在井眼中形成岩屑床，导致蹩泵、蹩钻甚至卡钻。本文在分析岩屑床的形成及危害的基础上，对岩屑床的清除办法进行了探讨，提出了将提高泥浆返速、改善泥浆性能与机械清除岩屑相结合的方法。胜利油田多口井的现场应用表明，该方法能有效地解决高难度定向井的携岩问题，为优质高效的钻高难度定向井提供了一定的技术保证。

关键词：定向井井斜位移岩屑钻井井眼

Reversing free-electron transfer of sulfide cocatalyst for exceptional photocatalytic H_(2)evolution

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Journal of Materials Science & Technology 2024年第4期171卷 147-149页

作者： Yanfeng zhang Zhenyi zhang National Experimental Chemistry Teaching Center Hebei Key Laboratory of Inorganic Nano-materialsCollege of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Recently,Yu and co-workers deeply explore the potential impact of free electron transfer between co-catalysts and photocatalyst carriers on H_(2)evolution efficiency of active sites over MoS_(2+x).They pro-pose an electron-reversal tactics to evade the unexpected electron transfer and synchronously regulate the above transfer in a beneficial orientation for weakening hydrogen adsorption on S ***,this highlight not only discusses and summarizes the essences of electron reversal and the optimized H ad-sorption/desorption mechanism,but also emphasizes the significance of femtosecond transient absorp-tion spectroscopy(fs-TAS)and in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)for revealing charge transfer dynamics and *** anticipate that this highlight can disseminate a new per-spective on the roles of photocatalyst carriers in improving cocatalytic H_(2)-production kinetics.

关键词： Photocatalysis Cocatalyst Electron reversal Antibonding-orbital occupancy S–H bonds

Kindlin-2 depletion disrupts smooth muscle structure and causes intestinal obstruction

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解剖学杂志 2021年第S1期44卷 177-177页

作者： He Xiaokun Zhan Jun zhang hongquan Department of Anatomy Histology and E mbryologyPeking University Health Science CenterBeijing 100191China

Kindlin-2 is widely expressed in striated and smooth muscle cells(SMC).However,the function of Kindlin-2 in smooth muscle remains ***,we demonstrate that depletion of Kindlin-2 encoding gene F ermt2 in smooth muscle leads to apoptosis,downregulates the key components of SMC,impairs smooth muscle development and finally embryonic death at *** en-induced Kindlin-2 knockout in adult mice show ed decreased blood pressure,intestinal hypoperistalsis,and eventully died of intestinal *** of Kindlin-2 also leads to shortened myofilament,decreased Myh1l,a-SMA and CNN,damaged ultrastructure and jeopardized contractility of the smooth muscle in iKO ***,loss of Kindlin-2 impairs Ca+influx in mouse primary vascular smooth muscle cells(PVSMC)by downregulating the expression of calcium bi nding protein S100A14 and STIM1.

关键词： Kindlin obstruction depletion