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Seismic damage zone and width-throw scaling along the strike-slip faults in the Ordovician carbonates in the Tarim Basin 被引量:12
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作者 De-Bo Ma Guang-Hui Wu +3 位作者 Nicola Scarselli Xin-Sheng Luo Jian-Fa Han Zhi-Yong Chen 《Petroleum Science》 SCIE CAS CSCD 2019年第4期752-762,共11页
Understanding the scaling relation of damage zone width with displacement of faults is important for predicting subsurface faulting mechanisms and fluid flow processes. The understanding of this scaling relationship i... Understanding the scaling relation of damage zone width with displacement of faults is important for predicting subsurface faulting mechanisms and fluid flow processes. The understanding of this scaling relationship is influenced by the accuracy of the methods and types of data utilized to investigate faults. In this study, seismic reflection data are used to investigate the throw and damage zone width of five strike-slip faults a ecting Ordovician carbonates of the Tarim intracraton basin,NW China. The results indicate that fault slips with a throw less than 200 m had formed wide damage zones up to 3000 m in width. Also, damage zone width is found to have both a positive correlation and a power-law relation with throw of two orders of magnitude, with a ratio of these values varying in a range of 2–15. The relationship between throw and damage zone width is not a simple power-law and changes its slope from small to larger size faults. The results indicate that throw scales well with damage zone width for the studied faults, and hence these can be used to predict fault geometries in the Tarim Basin. The study of the wide carbonate damage zones presented here provides new insights into scaling of large-size faults, which involve multiple faulting stages. 展开更多
关键词 Fault damage zone Carbonate throw SCALING Evolution Tarim Basin
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throw的含义及用法举隅
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作者 赵红梅 《川北教育学院学报》 2002年第3期68-69,共2页
关键词 英语教学 throw 含义 用法
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Sediment generation and soil mound denudation in areas of high-density tree throw along a river valley in the Jura Mountains, Switzerland
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作者 Philip GREENWOOD Jan BAUER Nikolaus J KUHN 《Journal of Mountain Science》 SCIE CSCD 2021年第2期377-391,共15页
A preliminary field-based investigation was undertaken in a small(<10 km^(2))river valley located in the mountainous Jura region of northwest Switzerland.The aims of the work were to assess sediment generation and ... A preliminary field-based investigation was undertaken in a small(<10 km^(2))river valley located in the mountainous Jura region of northwest Switzerland.The aims of the work were to assess sediment generation and annual sediment transport rates by tree throw on forested hillslopes,and to document surface hydrology characteristics on four fresh soil mounds associated with recent tree throws over a 24-day monitoring period.For the soil mounds,average sediment recovery ranged from 7.7-28.2 g(dry weight),equivalent to a suspended sediment concentration of 145.2-327.8 g L^(-1),and runoff coefficients ranged from 1.0%-4.2%.Based on a soil bulk density value of 1,044 kg m^(-3),upslope runoff generation areas were denuded by an average 0.14 mm by the end of the 24-day monitoring period,representing an erosion rate equivalent to 2.1 mm yr^(-1).A ca.50 cm high soil mound could therefore feasibly persist for around 200-250 years.For tree throw work,the dimensions of 215 individual tree throws were measured and their locations mapped in 12 separate locations along the river valley representing a cumulative area equivalent to 5.3 ha(av.density,43 per ha).Tree throws generated a total of 20.1 m^(3) of fine-sediment(<2 mm diameter),or the equivalent of 3.8×10^(-4) m^(3) m^(-2).The process of tree throw was originally attributed to two extreme weather events that occurred in west and central Europe in late December 1999.Taking the 18-year period since both storms,this represents an annual sediment transport rate of 2.7×10^(-5) m^(3) m^(-1) yr^(-1).Exploring the relationship with wind on fall direction,65.5%of tree throws(143)generally fell in a downslope direction irrespective of hillslope aspect on which they were located.This infers that individual storms may not have been responsible for the majority of tree throws,but instead,could be associated with root failure.Given the high density of tree throws and their relative maturity(average age 41 years),we hypothesise that once trees attain a certain age in this river valley,their physiognomy(i.e.height,mass and centre of gravity)compromises their ability to remain securely anchored.We tentatively attribute this possibility to the presence of bedrock close to the surface,and to the shallow soil profile overlaying steep hillslopes. 展开更多
关键词 Tree throw Hillslope processes Sediment generation mechanism Sediment transport rate Soil mound Ibach river valley
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Double Band Double-Pulley Repair for Articular Surface Partial Tears of the Supraspinatus in Throwing Athletes: Improving the Transtendon Technique
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作者 Osvaldo Garcia Martinez Eduard Buess Diosveny Gonzales Hernandez 《Open Journal of Orthopedics》 2012年第4期150-154,共5页
Disabled shoulders of throwing athletes typically present with extended undersurface partial tears of the rotator cuff, which include the posterior supraspinatus and the anterior infraspinatus tendon to a variable ext... Disabled shoulders of throwing athletes typically present with extended undersurface partial tears of the rotator cuff, which include the posterior supraspinatus and the anterior infraspinatus tendon to a variable extent. We propose a modified transtendon repair technique to adequately treat this subset of patients. The repair includes two double-loaded anchors, at the anterior and the posterior end of the tear, respectively. With the help of an angulated penetrator we create a medial and a lateral band of sutures on top of the cuff, producing a broad contact in the tendon-to-bone interface. All the 9 so far operated patients were young men, 7 of them base-ball pitchers, and 5 active in competitive sports. The Constant Score rose from 72 points preoperatively to 99 points at 12 months follow-up. Three of the still active pitchers were able to return to their previous level in sports after one year. The improved footprint contact of our novel repair construct should allow for better healing and, therefore, a higher chance of return to competition. 展开更多
关键词 Partial Tear SUPRASPINATUS Tendon throwING Athlete PASTA-Lesion PAINT-Lesion
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Kinematic Characteristics Analysis and Parametric Solving of Snow Melting Agent Throwing Mechanism with Variable Crank Length
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作者 Wenwu Liu Nianli Lu Hongxin Liu 《Journal of Harbin Institute of Technology(New Series)》 CAS 2021年第4期60-66,共7页
Variable crank length cam⁃linkage mechanism has attracted much attention due to its compact overall structure when realizing complex motion laws.According to the special trajectory requirements,the kinematic character... Variable crank length cam⁃linkage mechanism has attracted much attention due to its compact overall structure when realizing complex motion laws.According to the special trajectory requirements,the kinematic characteristics and parameters of the mechanism have been analyzed and solved,which lays foundation for the implementation of the variable crank length snow melting agent throwing mechanism designed in this paper.Based on the trajectory equation of the point,the mathematical model of the throwing mechanism was established,and the theoretical trajectory of the end point of the throwing mechanism was obtained by programming.The parametric modeling and trajectory drawing were carried out by computer aided three⁃dimensional interactive application(CATIA),and the correctness of the mathematical model was verified by comparison.The regional trajectory distribution characteristics of the end points of the throwing mechanism were studied by using the trajectory region location method,and the influence of various parameters on the trajectory was investigated by using the numerical cycle comparison method.The human⁃computer interaction system of snow melting agent throwing mechanism with variable crank length was constructed by using Microsoft Visual Basic(VB)software.Based on the restriction conditions,the optimum combination of structural adjustment parameters and operational parameters suitable for Harbin first⁃class roads was obtained by using orthogonal test table,which provides an effective method to solve the parameters of the variable crank length cam mechanism with smooth impulse trajectory. 展开更多
关键词 throwing mechanism variable crank length cam mechanism mathematical model kinematic characteristics parametric solving
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Appearance of Jiangzao 361, a Conventional Early Indica Rice Variety, in Throwing Demonstration Experiment and Its Matching Throwing Technique
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作者 胡金和 张志英 +4 位作者 祝飞 曾良明 彭裕建 胡玉平 杨小华 《Agricultural Science & Technology》 CAS 2017年第12期2331-2334,共4页
In this paper, the characteristics of Jiangzao 361, as well as its appear- ance in throwing transplanting are introduced, and the high-yielding throwing tech- nique for Jiangzao 361 is summed up. On the basis of the e... In this paper, the characteristics of Jiangzao 361, as well as its appear- ance in throwing transplanting are introduced, and the high-yielding throwing tech- nique for Jiangzao 361 is summed up. On the basis of the experimental demon- stration, the corresponding matching throwing technique is put forward. 展开更多
关键词 Conventional early indica rice Jiangzao 361 throwing technology
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A Bail-Out Plan Throws outfor SMEs
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作者 Li Zhen 《China's Foreign Trade》 2008年第Z3期32-,共1页
From the beginning of 2008,together with the appreciation of the RMB and the rising costs of labor and raw materials,tight monetary policies have contributed to the fi- nancial plight of small and medium-sized enterpr... From the beginning of 2008,together with the appreciation of the RMB and the rising costs of labor and raw materials,tight monetary policies have contributed to the fi- nancial plight of small and medium-sized enterprises(SMEs),especially those heav- ily reliant on exports. 展开更多
关键词 A Bail-Out Plan throws outfor SMEs
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A Corpus-based Comparative Study of the Semantic Collocations of English and Chinese THROW Verbs
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作者 李林夕 《海外英语》 2020年第6期94-95,共2页
A verb plays an vital role in a sentence, therefore the study of this perspective attracts numerous scholars. Particularly, corpus-based study has increasing attention in recent years. The present study chooses the TH... A verb plays an vital role in a sentence, therefore the study of this perspective attracts numerous scholars. Particularly, corpus-based study has increasing attention in recent years. The present study chooses the THROW verbs in both English and Chi?nese as the subject. The author applies"collocated"function or"pattern query"in two corpus, then analyzes the distinctions of the semantic collocation of the THROW verbs. The findings show that although these verbs belong to the same categorization in a limit?ed range of the specific histories and cultures, there is no one-to-one corresponding relation of these THROW verbs in translation across the two languages. 展开更多
关键词 throw VERB SEMANTIC COLLOCATION CORPUS-BASED study
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Stories of Horror Throws Light on Cruelty of Serfdom in Old Tibet
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作者 ZHIQING 《The Journal of Human Rights》 2003年第5期39-40,共2页
We are going to tell you some stories that took place in old Tibet, before the Democratic Reform in the late 1950s. about how, for the sole "crime" of being slaves or serfs, people had their limbs amputated,... We are going to tell you some stories that took place in old Tibet, before the Democratic Reform in the late 1950s. about how, for the sole "crime" of being slaves or serfs, people had their limbs amputated, eyes gouged out or noses cut off. These stories of horror might be beyond comprehension of any person with the least sense of human civilization, even though they are real. The system of serfdom practiced in old Tibet featured a combination of civil and 展开更多
关键词 in be on Stories of Horror throws Light on Cruelty of Serfdom in Old Tibet of
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Italian Textile Industry: Throw an Embroidered Ball in the Chinese Market
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作者 Ren Yan 《China Textile》 2009年第4期40-43,共4页
Throwing an embroidered ball is an act of seeking marriage practiced by noble family maidens in ancient China. March 2009, the early spring of Beijing saw Italian textile industry's passion for a close relationshi... Throwing an embroidered ball is an act of seeking marriage practiced by noble family maidens in ancient China. March 2009, the early spring of Beijing saw Italian textile industry's passion for a close relationship with the Chinese market after a global shiver in the freezing economic winter. It is a ball of elegance, quality and sincere cooperation, which is to become larger and more attractive with the stable development of Chinese textile industry and the ever expansion of Chinese consumption market. 展开更多
关键词 throw an Embroidered Ball in the Chinese Market Italian Textile Industry BALL
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Simulation and experimental research on line throwing rocket with flight 被引量:2
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作者 Wen-bin GU Ming LU +3 位作者 Jian-qing LIU Qin-xing DONG Zhen-xiong WANG Jiang-hai CHEN 《Defence Technology(防务技术)》 SCIE EI CAS 2014年第2期149-153,共5页
The finite segment method is used to model the line throwing rocket system.A dynamic model of line throwing rocket with flight motion based on Kane's method is presented by the kinematics description of the system... The finite segment method is used to model the line throwing rocket system.A dynamic model of line throwing rocket with flight motion based on Kane's method is presented by the kinematics description of the system and the consideration of the forces acting on the system.The experiment designed according to the parameters of the dynamic model is made.The simulation and experiment results,such as range,velocity and flight time,are compared and analyzed.The simulation results are basically agreed with the test data,which shows that the flight motion of the line throwing rocket can be predicted by the dynamic model.A theoretical model and guide for the further research on the disturbance of rope and the guidance,flight control of line throwing rocket are provided by the dynamic modeling. 展开更多
关键词 火箭系统 飞行运动 实验 仿真 动态模型 有限段方法 参数设计 飞行时间
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Optimization and experimental study of the auxiliary mechanism for organic fertilizer side throwing
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作者 Hongxin Liu Yongtao Xie +1 位作者 Yijian Zhao Jiajie Shang 《International Journal of Agricultural and Biological Engineering》 2025年第4期157-169,共13页
To correct the working state of a throwing component and achieve an ideal narrow,far,and uniform material projectile flow for a side-throwing device for organic fertilizer with inclined opposing discs,a systematic opt... To correct the working state of a throwing component and achieve an ideal narrow,far,and uniform material projectile flow for a side-throwing device for organic fertilizer with inclined opposing discs,a systematic optimization of the auxiliary mechanisms(baffle,upper deflector,and side deflector)was performed.Starting from a basic analysis of the working principles of each side-throwing device component,theoretical modeling and MATLAB numerical calculations were used to determine the departure angle providing the farthest fertilizer distance,as well as the maximum and minimum throwing angles required to achieve a target distance of 10 m.These calculations informed the optimization and configuration of the basic structures of each auxiliary mechanism component.The impact of the baffle on fertilizer movement was analyzed,leading to an optimization of the baffle’s height and its horizontal position in relation to the main throwing disc,guiding the design of the discharge port structure.Combining the theoretical analysis results,the surface of the upper deflector was fitted,and a side deflector was added to assist in limiting the scattering angle of the projectile flow.An EDEM simulation showed that the optimized auxiliary mechanisms worked well together,resulting in a narrower discharge width,a more concentrated projectile flow,and improved uniformity in spreading.Prototype testing confirmed that from the side projection angle between the spreading direction and vertically upward,the projectile flow angle domain was adjusted from 18°-45°to 23°-32°.With the optimization of other auxiliary mechanisms,the coefficient of variation in spreading uniformity decreased from 25.95%to 19.21%,the effective throwing distance increased from 10.1 to 11.2 m,and the scattering angle decreased from 12°to 4°,effectively enhancing the performance of the side-throwing device. 展开更多
关键词 organic fertilizer side throwing auxiliary mechanism optimization research virtual simulation EXPERIMENT
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蔬菜密植移栽斜置式自动取投苗装置设计与试验 被引量:2
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作者 白晓虎 杜国静 +3 位作者 张子浩 邱硕 赵博 田素博 《农业机械学报》 北大核心 2025年第5期300-308,共9页
针对密植蔬菜半自动移栽作业效率低的问题,本文设计一种用于A5-1200型高密度移栽机斜置式自动取投苗装置。钵苗盘和取投臂均与水平方向倾斜45°布置,取投苗爪在取苗位置和投苗位置之间直线往复运动,缩短了取苗行程。取投苗爪在取投... 针对密植蔬菜半自动移栽作业效率低的问题,本文设计一种用于A5-1200型高密度移栽机斜置式自动取投苗装置。钵苗盘和取投臂均与水平方向倾斜45°布置,取投苗爪在取苗位置和投苗位置之间直线往复运动,缩短了取苗行程。取投苗爪在取投臂上的安装位置固定,与钵苗间距和投苗杯间距对应,省略了分苗环节。钵苗盘移位机构通过横向移动和纵向移动将钵苗输送到取苗位置,实现整排间隔取苗。传动部件采用滚珠丝杠模组,驱动采用步进电机,以PLC为控制器,实现了运动位置精确控制。通过单因素试验分析取投臂回程速度、取投苗爪插入深度和取投苗爪入土角对取投苗效果的影响规律,设计Box-Behnken响应面试验确定最优工作参数。试验结果表明,当取投臂回程速度为300 mm/s、取投苗爪插入深度为31 mm、取投苗爪入土角为10°时,实际取投成功率为97.0%。配备斜置式自动取投苗装置后,A5-1200型高密度移栽机栽植能力可达到7200株/h,满足密植移栽技术要求。 展开更多
关键词 移栽机 密植移栽 斜置式 取投苗装置 移位机构
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我国“高空抛坠物”侵权规则适用的三段证成——兼论《民法典》第1254条适用的司法范式 被引量:1
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作者 郑志涛 《海南大学学报(人文社会科学版)》 2025年第1期142-150,共9页
通过检视现行立法规范和实务适用逻辑,针对司法范式缺陷与适用困境,结合民法解释学,在大前提、小前提和结论三段结构中论证“高空抛坠物”侵权责任的法律适用,有助于提升司法裁判的可预期性。“小前提”系侵权案件事实,“大前提”系《... 通过检视现行立法规范和实务适用逻辑,针对司法范式缺陷与适用困境,结合民法解释学,在大前提、小前提和结论三段结构中论证“高空抛坠物”侵权责任的法律适用,有助于提升司法裁判的可预期性。“小前提”系侵权案件事实,“大前提”系《民法典》第1254条之规定,“法律解释”系“大前提”和“小前提”之连结。将法律解释置于“大前提”和“小前提”之间,并推导“结论”的三段论证,有助正本溯源,统一类案之间法律适用。首先,由法律解释确定某法律规范是否适用;其次,通过法律解释规范“大前提”对“小前提”的理解和适用;最后,形成稳定的司法范式得出符合预期的“结论”。 展开更多
关键词 高空抛坠物 侵权责任 公平责任
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大滚筒智能钓机出绳速度控制及其对长鳍金枪鱼捕捞效果的影响
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作者 刘雨青 吴世腾 +2 位作者 宋利明 伏州 张子宸 《上海海洋大学学报》 北大核心 2025年第2期282-294,共13页
自动化捕捞装备的研发是推动远洋捕捞渔业高质量发展的关键要素,为了提升远洋作业中金枪鱼捕捞效率和渔获质量,提出了一种基于南太平洋长鳍金枪鱼(Thunnus alalunga)延绳钓钓钩深度模型设计的智能投绳控制系统。该系统采用模糊比例积分... 自动化捕捞装备的研发是推动远洋捕捞渔业高质量发展的关键要素,为了提升远洋作业中金枪鱼捕捞效率和渔获质量,提出了一种基于南太平洋长鳍金枪鱼(Thunnus alalunga)延绳钓钓钩深度模型设计的智能投绳控制系统。该系统采用模糊比例积分微分(Proportion integral differential,PID)控制方式,结合作业渔船部署的传感器采集实时数据,通过可编程逻辑控制器(Programmable logic controller,PLC)实时调节投绳机的出绳速度,使钓钩深度达到目标鱼种的栖息深度。首先采用仿真实验及验证实验证实模糊PID在智能投绳控制系统的有效性,然后在中水集团远洋股份有限公司所属的“中水747”渔船上部署该系统进行海试试验,通过智能投绳控制系统作业与传统人工作业两种方式对比出绳速度控制精度及稳定性、钓钩深度及渔获情况。结果显示:(1)系统能根据船速自动调节出绳速度,将稳态误差控制在2%左右;(2)最深钓钩平均深度为230.20 m,两浮子间53.57%的钓钩深度与长鳍金枪鱼的捕食深度重合;(3)长鳍金枪鱼上钩率提高了31.85%,目标渔获的优势体质量区间由(14,18]kg提升至(18,22]kg,渔获质量及效率显著提升。研究表明,智能投绳控制系统作业优于传统人工作业,可有效提升金枪鱼目标鱼种的捕捞效率。本研究为金枪鱼捕捞装备的智能化控制提供了科学依据,推动了远洋渔业装备的技术创新与智能化升级。 展开更多
关键词 长鳍金枪鱼 智能投绳控制系统 模糊PID 出绳速度 捕捞效率
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电路板通孔电镀铜四硝基四氮唑蓝抑制剂的模拟研究
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作者 杨广柱 谢军 +4 位作者 陈德灯 雷艺 韦相福 胡小强 方正 《电镀与精饰》 北大核心 2025年第3期39-46,共8页
采用模拟与实验方法研究了四硝基四氮唑蓝(TNBT)抑制剂对柔性电路板浅通孔电镀铜的均镀能力(TP)的影响。首先采用分子动力学(MD)模拟研究了TNBT抑制剂在Cu(111)表面的吸附行为,进一步使用密度泛函理论(DFT)计算揭示了TNBT抑制剂的吸附机... 采用模拟与实验方法研究了四硝基四氮唑蓝(TNBT)抑制剂对柔性电路板浅通孔电镀铜的均镀能力(TP)的影响。首先采用分子动力学(MD)模拟研究了TNBT抑制剂在Cu(111)表面的吸附行为,进一步使用密度泛函理论(DFT)计算揭示了TNBT抑制剂的吸附机制,最后通过电镀实验探明了TNBT抑制剂对通孔电镀TP值的影响规律。结果表明:TNBT分子主要通过苯甲醚和硝基苯等活性位点与Cu(111)表面发生化学吸附作用;TNBT分子的吸附行为主要由其前沿分子轨道分布的官能团所主导;TNBT分子展现较强的铜沉积抑制作用,并显著提高浅通孔电镀的TP值。该抑制剂有效克服了传统添加剂过度依赖对流环境的缺点,能满足浅通孔的超高TP值电镀要求。 展开更多
关键词 柔性电路板 通孔电镀 均镀能力 添加剂
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装药不耦合系数对台阶爆破破碎块体抛掷运动规律影响研究
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作者 黄永辉 阮迅 +3 位作者 雷振 毛泽凌 张智宇 周继国 《工程科学与技术》 北大核心 2025年第2期223-233,共11页
露天台阶爆破中破碎块体时空运动规律及能耗是衡量爆破效果的重要指标之一,针对不耦合系数改变情况下破碎块体运动速度和能耗问题,采用基础理论方法,通过破碎块体运动轨迹构建能耗计算公式,并结合模型试验,对不同不耦合系数情况下的爆... 露天台阶爆破中破碎块体时空运动规律及能耗是衡量爆破效果的重要指标之一,针对不耦合系数改变情况下破碎块体运动速度和能耗问题,采用基础理论方法,通过破碎块体运动轨迹构建能耗计算公式,并结合模型试验,对不同不耦合系数情况下的爆破破碎块体运动速度变化规律及能耗情况开展系统研究。结果表明:起爆后,岩体在约2 ms时初步产生裂隙,约20 ms时加速完成;岩体自由表面呈现上下两侧低、中间高的鼓包形态;破碎块体的速度随着时间呈现加速—动态匀速—抛掷减速3个过程,并且在18 ms左右达到初始抛掷速度和抛掷动能,此后破碎块体基本不受爆生产物的作用;通过计算获得了不同不耦合系数条件下的抛掷动能值,其占炸药总能量的比例为5%~16%;抛掷动能及其占比随着不耦合系数的增大而减小,当不耦合系数从1.250增至3.375时,抛掷动能从3.06 kJ减小到1.12 kJ,抛掷动能占比从15.3%减小到5.6%。研究成果对露天台阶爆破不耦合装药条件下的岩体破碎、破碎块体运动规律及能耗分布研究具有理论指导意义和工程应用价值。 展开更多
关键词 不耦合系数 台阶爆破 运动速度 抛掷动能 高速摄影仪
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一种抛料机传动装置的优化设计
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作者 周林军 张国勇 《化工装备技术》 2025年第3期39-42,共4页
抛料机是冶金企业沸腾焙烧系统的关键设备,也是沸腾焙烧炉的关键环节,但其故障频发,曾多次导致沸腾炉停炉。针对抛料机皮带跑偏、烧毁等问题,分析了抛料机的结构组成及皮带跑偏、严重磨损和掉落的原因,提出了以下优化措施:优化滚筒固定... 抛料机是冶金企业沸腾焙烧系统的关键设备,也是沸腾焙烧炉的关键环节,但其故障频发,曾多次导致沸腾炉停炉。针对抛料机皮带跑偏、烧毁等问题,分析了抛料机的结构组成及皮带跑偏、严重磨损和掉落的原因,提出了以下优化措施:优化滚筒固定座结构,增加气幕装置,增大压带轮倒圆角和外径,降低皮带温度,并减少跑偏和磨损的频次。生产实践表明,优化后抛料机振动显著减弱,运行平稳,未出现张紧螺杆滑丝松动现象;皮带烧毁问题得到有效控制,皮带软化压死和跑偏现象明显减少,故障率大幅降低;检修方便,年检修费用从65.92万元降至9.3万元,节约成本56.62万元,经济效益显著。 展开更多
关键词 抛料机 带传动 热辐射 磨损
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基于DEM-MBD的双轨迹钻井液振动筛筛分性能研究
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作者 吕志鹏 段铃童 +2 位作者 韩庆锋 杨令 闵庆新 《石油机械》 北大核心 2025年第8期44-52,59,共10页
为增强振动筛的处理能力,满足钻采过程中的不同工况需求,改善现有钻井液振动筛存在的“筛堵”“跑浆”等问题,提出了一种“直线+变椭圆”的双轨迹钻井液振动筛,并基于离散元方法 (discrete element method, DEM)耦合多体系统动力学(dyna... 为增强振动筛的处理能力,满足钻采过程中的不同工况需求,改善现有钻井液振动筛存在的“筛堵”“跑浆”等问题,提出了一种“直线+变椭圆”的双轨迹钻井液振动筛,并基于离散元方法 (discrete element method, DEM)耦合多体系统动力学(dynamics of multi-body system,MBD)的研究方法,对双轨迹振动筛和岩屑颗粒进行联合仿真计算。探究了2种振型下筛网面上的运动轨迹与抛掷指数、筛分过程中多种岩屑颗粒的运动行为以及筛分性能。研究结果发现:变椭圆轨迹下从入料端至出料端筛面的抛掷指数和振动方向角逐渐减小,有利于实现入料端钻井液固液分离与液相透筛,降低出料端岩屑颗粒的破碎和堵筛概率;稳定筛分时,易透筛颗粒基本处于料层底部或已经透筛,难透筛和不透筛颗粒处于料层的中上层;变椭圆轨迹下多种岩屑颗粒的透筛率均高于直线轨迹、平均透筛时间均短于直线轨迹、平均运移速度均大于直线轨迹。研究成果可为钻井液振动筛的性能提升提供参考。 展开更多
关键词 双轨迹振动筛 变椭圆 离散元法 筛分特性 耦合多体系统动力学 岩屑颗粒 抛掷指数
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某型装备抛未击发弹故障原因及处置研究
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作者 程杰 《舰船电子工程》 2025年第4期15-17,37,共4页
以实际案例引出某型装备抛未击发弹故障,介绍了某型装备故障处置应遵循的一般原则,重点阐述了抛未击发弹故障现象、原因及在实装上复现该故障的方法步骤。在此基础上,叙述了抛未击发弹故障的具体排除方法与注意事项,以期通过该故障处置... 以实际案例引出某型装备抛未击发弹故障,介绍了某型装备故障处置应遵循的一般原则,重点阐述了抛未击发弹故障现象、原因及在实装上复现该故障的方法步骤。在此基础上,叙述了抛未击发弹故障的具体排除方法与注意事项,以期通过该故障处置对策研究对同类装备故障处置与排除起到一定的启示作用。 展开更多
关键词 装备 抛未击发弹 处置
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