Results 21 to 30 of about 3,003 (166)
Shiyou jixie, 2012 鉴于直流电驱动钻机功率因数低且波动较大、谐波污染较大、干扰其他设备和直流电动机维护多于交流电动机等状况，介绍了河南油田电动钻机控制系统的配置，剖析了控制系统在现场运行中出现的问题与原因，并提出采用进口的电气元件、选择具备在特殊环境下工作能力的制冷装置、加大对操作员工的岗位培训力度、加强现场设备的巡回检查和强制设备保养制度、加装动态无功补偿与谐波抑制装置等优化方案，提高了整机设备动、静态性能，实现了电驱动钻机安全、可靠运行，在河南油田持续有效、和谐发展的局面中发挥着更大优势。
万广伟 +4 more
doaj
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT The evolution of the γ′−Ni3(Al, Ti) phase in superalloys is governed by a coupled coalescence‐ripening mechanism driven by elemental diffusion. In this study, thermal exposure experiments were performed at 750°C and 800°C for durations ranging from 100 to 20,000 h.
Zhaotian Wang +5 more
wiley +1 more source
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT High‐entropy alloys (HEAs) have attracted considerable interest from researchers owing to their tunable chemical compositions, exceptional structural stability, and promising catalytic properties. However, their large‐scale application is often hindered by complex manufacturing techniques and poor durability.
Sheng Guo +9 more
wiley +1 more source
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT The development of efficient and stable bifunctional catalysts remains a key challenge for green hydrogen production via electrochemical water splitting. In this study, a bimetallic Mo/Fe‐doped CoP2 nanoleaf array anchored on carbon cloth (Mo, Fe‐CoP2@CC) was synthesized from zeolitic imidazolate framework‐L (ZIF‐L) via an ion‐exchange and low‐
Xiangqun Zeng +6 more
wiley +1 more source
Shiyou jixie, 2012 针对目前油田为各型修井机提供动力的柴油机的工作效率仅为50%，不仅作业成本高，而且还存在噪声污染和排放废气等问题，研制了XJ40型橇装式电驱动修井机。〖JP2〗该电驱动修井机采用模块化设计，整机分为调速电动机及控制模块、传动系统模块、绞车及盘式刹车模块、液压控制模块及橇装底盘等5大模块，具有结构简单、占地面积小、操作方便和环保节能等优点。现场试验结果表明，采用该修井机进行一般的修井作业，工作效率比传统的通井机、修井机高10%左右，动力费用约为传统修井作业设备的523%，无废气排放，噪声低 ...
马西庚 +4 more
doaj
Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT The construction of p–n homojunctions represents a promising strategy for effective solar‐driven photocatalytic hydrogen evolution, owing to their inherent advantages of superior lattice matching and minimized charge transfer resistance. However, this approach remains largely unexplored.
Yueqiang Lin +6 more
wiley +1 more source
智能科学与技术学报, 2019 空间智能软体机械臂因其结构轻巧、灵活可变、可折叠收缩等特性，在航天器在轨服务任务中，将具有广阔的应用前景。首先提出了一种全向驱动的模块化软体机械臂设计方案，利用刚柔耦合动力学理论建立了气控驱动的软体机械臂动力学模型，基于深度回归卷积神经网络理论建立了空间非合作目标检测与识别算法，为空间软体机械臂智能控制奠定了技术基础。进一步地，设计并研制了软体机械臂地面原理样机及其试验系统，通过地面试验，对软体机械臂的自主运动控制和识别算法进行了初步验证。
张翔 +5 more
doaj
Functional Ecology, Volume 40, Issue 3, Page 750-763, March 2026.Read the free Plain Language Summary for this article on the Journal blog. Abstract Forests worldwide are increasingly impacted by drought due to climate change, prompting plants to adapt through dehydration tolerance (DT) and avoidance (DA), two distinct physiological strategies.
Xingyun Liang +11 more
wiley +1 more source
Guangtongxin yanjiu, 1991 本文报道一种适合用现有工艺条件进行研制的OEIC光发送机的驱动电路。该驱动电路不仅对信号具有一定的整形能力,而且更适于高速脉码调制。同时,当制作工艺条件变化时具有较高的稳定性。对该电路进行计算机辅助分析和优化,得到该电路的上升、下降时间为120ps、140ps。
陈维友, 胡礼中, 刘式墉
doaj
Functional Ecology, Volume 40, Issue 3, Page 636-654, March 2026.Read the free Plain Language Summary for this article on the Journal blog. Abstract The nested subset pattern (nestedness) has been widely used to explain species distributions in island and fragmented systems. Mountain sky islands serve as critical natural laboratories for understanding the evolutionary consequences of geographic isolation and climate
Caiwen Zhang +5 more
wiley +1 more source