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土壤源热泵技术实际应用中的经验分析

山西建筑 2014年第14期40卷 135-136页

作者：纪怀忠山西国瑞房地产开发有限公司山西太原030006

对土壤源热泵技术的适用条件进行了分析,介绍了土壤源热泵技术初投资的组成部分,并探讨了该技术在实际应用中有待解决的问题,提出了合理使用该技术的技巧,使其得到进一步的推广应用。

关键词：土壤源热泵技术投资地下水

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谈房地产开发项目建设全过程管理

山西建筑 2013年第17期39卷 214-215页

作者：纪怀忠山西国瑞投资有限公司山西太原030006

针对房地产开发项目周期长、投资大、风险多等特点,从项目开发前期、建设期、交付使用及后期维护等方面入手,对房地产开发项目管理进行了研究,以期使房地产企业开发出优质的房地产产品。

关键词：房地产项目管理开发建设

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铬对高速车轮钢显微组织和力学性能的影响

钢铁研究学报 2006年第8期18卷 39-42页

作者：崔银会范映潘涛季怀忠安徽工业大学材料学院安徽马鞍山243000 钢铁研究总院结构材料研究所北京100081 马鞍山钢铁股份有限公司安徽马鞍山243000

研究了微量铬对高速车轮钢组织和性能的影响。实验结果显示,加入微量的铬,可以细化珠光体的片层间距,在保持韧塑性基本不变的情况下,显著增加材料的强度和硬度,从而提高车轮钢的耐磨性和抗剥离性能。

关键词：车轮钢铬硬度片层间距

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车轮钢摩擦热影响区的相变及其损伤机理

钢铁研究学报 2005年第4期17卷 55-59页

作者：季怀中苏航杨才福张永权钢铁研究总院结构材料研究所

将有限元热力耦合-温度场分析与材料相变特征的实验研究相结合,研究了高速度(200km/h)、大载荷(105N)条件下车轮摩擦热影响区的相变过程,探讨了材料对该过程的影响。结果表明,轮-轨摩擦导致的车轮踏面局部升温可超过材料的奥氏体相变的... 详细信息

将有限元热力耦合-温度场分析与材料相变特征的实验研究相结合,研究了高速度(200km/h)、大载荷(105N)条件下车轮摩擦热影响区的相变过程,探讨了材料对该过程的影响。结果表明,轮-轨摩擦导致的车轮踏面局部升温可超过材料的奥氏体相变的临界点,碳含量为0·5%时,完全奥氏体化层的深度可达0·6mm;过冷奥氏体高速冷却,几乎全部形成脆硬的马氏体薄层,造成踏面剥离。通过降碳来降低车轮钢奥氏体相变的临界点,可以显著抑制踏面马氏体层的形成。随着碳含量从0·7%降至0·4%,材料的Ac3提高45℃,马氏体层的厚度减小30%,有助于减少车轮踏面的热疲劳损伤。

关键词：车轮钢热疲劳马氏体相变摩擦有限元分析

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碳含量对高速车轮用钢综合性能的影响

钢铁 2005年第2期40卷 62-65,81页

作者：季怀忠崔银会苏航张永权水恒勇马鞍山钢铁股份有限公司技术中心安徽马鞍山243000 钢铁研究总院结构材料研究所北京100081

研究了碳的质量分数在 0 .4 %～ 0 .7%的范围内变化时对高速列车车轮用钢综合性能的影响。结果表明 ,随着碳含量的增加 ,试验钢的耐磨性能和接触疲劳性能提高 ,而冲击韧性及抗冷热疲劳性能降低 ;在 880℃正火 +5 30℃回火的热处理条件... 详细信息

研究了碳的质量分数在 0 .4 %～ 0 .7%的范围内变化时对高速列车车轮用钢综合性能的影响。结果表明 ,随着碳含量的增加 ,试验钢的耐磨性能和接触疲劳性能提高 ,而冲击韧性及抗冷热疲劳性能降低 ;在 880℃正火 +5 30℃回火的热处理条件下 ,碳的质量分数为 0 .5 %并添加少量合金元素的试验钢 ,具有良好的强韧性匹配 ,特别是抗冷热疲劳和抗接触疲劳性能良好 ,并兼有较好的耐磨性能 ,综合性能优良 ,较适宜于生产具有抗剥离性要求的高速车轮钢。

关键词：车轮碳含量疲劳损伤耐磨性高速列车

High‑Entropy Electrode Materials:Synthesis,Properties and Outlook

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Nano-Micro Letters 2025年第1期17卷 472-506页

作者： Dongxiao Li Chang Liu Shusheng Tao jieming Cai Biao zhong jie Li Wentao Deng Hongshuai Hou Guoqiang Zou Xiaobo ji College of Chemistry and Chemical Engineering Central South UniversityChangsha 410083People’s Republic of China School of Chemistry and Chemical Engineering Hunan Institute of EngineeringXiangtan 411104People’s Republic of China

High-entropy materials represent a new category of high-performance materials,first proposed in 2004 and extensively investigated by researchers over the past two *** definition of high-entropy materials has continuously *** the last ten years,the discovery of an increasing number of high-entropy materials has led to significant advancements in their utilization in energy storage,electrocatalysis,and related domains,accompanied by a rise in techniques for fabricating high-entropy electrode ***,the research emphasis has shifted from solely improving the performance of high-entropy materials toward exploring their reaction mechanisms and adopting cleaner preparation ***,the current definition of high-entropy materials remains relatively vague,and the preparation method of high-entropy materials is based on the preparation method of single metal/low-or medium-entropy *** should be noted that not all methods applicable to single metal/low-or medium-entropy materials can be directly applied to high-entropy *** this review,the definition and development of high-entropy materials are briefly ***,the classification of high-entropy electrode materials is presented,followed by a discussion of their applications in energy storage and catalysis from the perspective of synthesis ***,an evaluation of the advantages and disadvantages of various synthesis methods in the production process of different high-entropy materials is provided,along with a proposal for potential future development directions for high-entropy materials.

关键词： High-entropy Energy storage Electrode materials

Experimental studies on rock failure mechanisms under impact load by single polycrystalline diamond compact cutter

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Petroleum Science 2023年第5期20卷 3100-3109页

作者： Zhao-Sheng ji jin-Bao jiang huai-zhong Shi Bang-Min Li Drilling Engineering Technology Research Institute Sinopec Zhongyuan Petroleum Engineering CompanyPuyangHenan457001China State Key Laboratory of Petroleum Resources and Prospecting Beijing102249China

Percussive drilling shows excellent potential for promoting the rate of penetration(ROP)in drilling hard *** diamond compact(PDC)bits account for most of the footage drilled in the oil and gas *** reveal the rock failure mechanisms under the impact load by PDC bits,a series of drop tests with a single PDC cutter were conducted to four kinds of rocks at different back rake angles,drop heights,drop mass,and drop *** the morphology characteristics of the craters were obtained and quantified by using a three-dimensional *** fracture micrographs can be observed by using scanning electron microscope(SEM).The distribution and propagation process of subsurface cracks were captured in rock-like silica glass by a high-speed photography *** results can indicate that percussive drilling has a higher efficiency and ROP when the rock fractures in brittle *** failure mode of rock is related with the type of rock,the impact speed,and the back rake angle of the *** the penetration depth and fragmentation volume get the maximum values at a back rake angle of about 45°.Increasing the weight and speed of falling hammer is beneficial to improving the rock breaking effects and *** subsurface cracks under the impact load by a single PDC cutter is shaped like a clamshell,and its size is much larger than the crater *** findings can help to shed light on the rock failure mechanisms under the impact of load by a single PDC cutter and provide a theoretical explanation for better field application of percussive drilling.

关键词： Percussive drilling PDC cutter Drop test Failure mechanism Subsurface cracks

Investigations into the coiled tubing partial underbalanced drilling (CT-PUBD)technique for drilling hard formations

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Petroleum Science 2018年第4期15卷 830-840页

作者： huai-zhong Shi Zhao-Sheng ji He-Qian Zhao Heng-Yu Song Zhen-Liang Chen State Key Laboratory of Petroleum Resources and Prospecting Beijing 102249China College of Petroleum Engineering China University of Petroleum (Beijing)Beijing 102249China

To improve the rate of penetration(ROP) in drilling deep and hard formations, this paper proposes a new drilling method called coiled tubing partial underbalanced drilling(CT-PUBD). As a preliminary investigation into the new drilling method, this paper presents predictions of hole cleaning efficiency, drilling speed, cuttings migration and pressure loss in the drilling process with CT-PUBD. Based on numerical simulation and full-scale experimental studies, we conclude that using CT-PUBD, an underbalanced drilling condition can be achieved near the bit while maintaining wellbore safety at the same time. This condition can be achieved using a cuttings discharge device, a rotary packer and a backflow *** to the numerical simulations performed in this study, CT-PUBD can achieve high efficiency of hole *** the cuttings migration process, the fluid velocities can reach the maximum values in the backflow holes. A full-scale laboratory experimental system was used to test the hydraulic characteristics and obtain the drilling performance of the new technology. The result shows that CT-PUBD significantly improves the ROP compared to the conventional drilling method.

关键词： Partial underbalanced drilling Coiled tubing Flow fields Cuttings removal Rate of penetration(ROP)

Strongly Irreducible Operators on Banach Spaces

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Acta Mathematica Sinica,English Series 2012年第4期28卷 727-740页

作者： Yun Nan ZHANG huai jie zhong School of Mathematics and Computer Science Fujian Normal University Mathematics and Information Science College Hebei Normal University

This paper firstly discusses the existence of strongly irreducible operators on Banach spaces. It shows that there exist strongly irreducible operators on Banach spaces with w＊-separable dual. It also gives some properties of strongly irreducible operators on Banach spaces. In particular, if T is a strongly irreducible operator on an infinite-dimensional Banach space, then T is not of finite rank and T is not an algebraic operator. On Banach spaces with subsymmetric bases, including infinite-dimensional separable Hilbert spaces, it shows that quasisimilarity does not preserve strong irreducibility. In addition, we show that the strong irreducibility of an operator does not imply the strong irreducibility of its conjugate operator, which is not the same as the property in Hilbert spaces.

关键词： Banach spaces strongly irreducible operators w*-separable quasisimilar