Results 1 to 10 of about 10,200 (111)
Zhejiang Daxue xuebao. Lixue ban, 2013 采用高效液相色谱研究了不同溶剂体系中褶皱假丝酵母菌脂肪酶(CRL)催化布洛芬乙烯酯水解反应的立体选择性.研究发现，在单一溶剂体系中Eyring曲线呈线性，在10~50 ℃的实验温度内均呈S选择性；在混合溶剂体系中Eyring曲线呈非线性，且观察到不同的转变温度(Tinv).研究还发现：在亲水性有机溶剂二氧六环/水均相混合溶剂体系中，Eyring曲线的Tinv处立体选择性E值为极小值，在疏水性有机溶剂异辛烷/水两相混合溶剂体系中，Tinv处E值为极大值，而在氯仿/水两相混合溶剂体系中，随着温度的变化 ...
WANGTing-ting(王婷婷) +3 more
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Zhejiang Daxue xuebao. Lixue ban, 2015 将多壁碳纳米管负载的碳化钼催化剂用于玉米油的加氢脱氧反应以制备柴油类烃，结果表明，该类催化剂对玉米油加氢脱氧反应具有极高的转化率和选择性.结合XRD、Raman、TEM、IR、TG等催化剂表征技术，考察了载体多壁碳纳米管的预处理条件、管径、表面缺陷浓度等因素对催化剂活性和玉米油加氢脱氧反应的影响.在氢压2.5 MPa、反应温度260 ℃、搅拌速率500 r • min-1的实验条件下反应3 h后，玉米油在Mo2C/MWCNT上加氢脱氧制备柴油类烃的反应转化率接近90%，烃类选择性达到了98%.
CAODanyan(曹丹艳) +3 more
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Dizhen xuebao地震观测中会遇到台站出现时钟错误和波形极性反转等问题，需要在地震数据处理过程中对其进行检测和校正。基于此，本文提出了一种基于地震面波相位测量和P波到时检测台站时钟错误和极性反转的方法，并使用该方法检测了全球30个台网的2 010个台站2008—2012年期间记录到的MW≥5.5事件的长周期地震波形数据，对处理效果进行分析。结果显示，12个台站的14个时段出现大于10 s的时钟错误，7个台站的8个时段发生了波形极性反转，表明此方法可以快速准确地检测出地震台站出现的较大时钟错误和极性反转的时段 ...
Shun Zhao +4 more
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Gaoya dianqi, 2023 绝缘子表面积聚的电荷会畸变电介质表面电场进而引发沿面闪络。为研究空气氛围中绝缘介质表面在沿面流注放电发展过程中动态电荷积聚情况，在自主开发的二维流体沿面放电仿真模型中增加化学反应体系，模拟了正负极性沿面放电在起始及发展过程中流注自身特性以及介质表面电荷分布特性的演化过程。研究发现施加电压为负极性时，介质表面始终累计负电荷，沿面流注头部累积电荷量极高，流注头部后方界面处电场极性反转，正离子向介质表面运动；施加电压为正极性时，沿面流注头部累积正电荷，尾部电子朝介质表面扩散，介质表面总电荷量为负值。
李晓冉 +3 more
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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
Gaoya dianqi, 2023 为调控直流稳态与极性反转工况下直流气体绝缘输电线路（HVDC GIL）绝缘子的沿面电场分布，分别设计了稳态梯度（ST-SFGM）绝缘子与极反梯度（PR-SFGM）绝缘子。迭代优化后的SFGM绝缘子涂层电导率恒定，厚度沿r坐标方向减小。电场仿真结果表明，直流稳态工况下均匀绝缘子的最大电场出现在高压三结合点附近，强度为4.25 kV/mm。ST-SFGM绝缘子与PR-SFGM绝缘子的直流电场分布较为均匀，最大电场强度分别下降54.6%与62.1%。极性反转工况下，均匀绝缘子与ST ...
姚航, 杜伯学, 梁虎成, 董佳楠
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Bidirectional Interfacial Chemical Regulation Enables Durable Aqueous Zn‐I2 Batteries
Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT Aqueous Zn‐I2 batteries hold great promise for large‐scale energy storage, yet their practical deployment is hindered by coupled interfacial instabilities at both electrodes, where Zn‐anode parasitic reactions and cathodic polyiodide shuttle mutually aggravate each other.
Zimian Jia +8 more
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Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT Non‐noble metal oxygen electrocatalysts are essential for low‐cost rechargeable metal‐air batteries and fuel cells, determining their energy conversion efficiency. However, such electrocatalysts are limited by inadequate bifunctional activity and stability toward the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER).
Lixin Sun +14 more
wiley +1 more source
Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT Magnesium hydride (MgH2) is a promising solid‐state hydrogen storage material due to its high gravimetric capacity and excellent reversibility. However, its practical application is hindered by high thermodynamic stability and sluggish reaction kinetics.
Xingyang Chen +6 more
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Rare Metals, Volume 45, Issue 9, September 2026.ABSTRACT Developing electrode materials with high capacity and outstanding activity is essential for energy storage and conversion technologies. However, integrating multiple functions into a single material remains challenging. Herein, we synthesized a novel CoP@NiCo layered double hydroxide (CoP@NiCo‐LDH) nano‐electrode using hydrothermal and ...
Ruiyu Li +9 more
wiley +1 more source