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Effect of Cutting Techniques on the Structure and Magnetic Properties of a High-grade Non-oriented Electrical Steel 被引量:1
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作者 石文敏 刘静 LI Changyi 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第6期1246-1251,共6页
The high grade non-oriented electrical steel sheets containing 3.0%Si were manufacturing processed using different cutting techniques, then they were stress relief annealed(SRA), the profiles and textures of the cut... The high grade non-oriented electrical steel sheets containing 3.0%Si were manufacturing processed using different cutting techniques, then they were stress relief annealed(SRA), the profiles and textures of the cutting edges were compared before and after annealing, and the magnetic properties of these specimens were tested and compared. The experimental results show that the iron loss of the specimen by water jet cutting is the lowest, but the magnetic induction under the low magnetic field is the highest, the iron loss of the specimen by laser cutting is the highest, but the magnetic induction under the low magnetic field is the lowest. It is necessary to adopt suitable production conditions and minimize the deterioration involved, and the magnetic property can be recovered by SRA effectively. 展开更多
关键词 non oriented electrical steel cutting techniques iron loss magnetic induction SRA
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Cutting and Welding of High-Strength Steels Using Non-Vacuum Electron Beam as a Universal Tool for Material Processing 被引量:1
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作者 Thomas Hassel Nils Murray +1 位作者 Georgii Klimov Alexander Beniyash 《World Journal of Engineering and Technology》 2016年第4期598-607,共11页
Using a non-vacuum electron beam, a two-step process chain for plate materials is a feasible possibility. Cutting and welding can be performed in subsequent steps on the same machine for a highly productive process ch... Using a non-vacuum electron beam, a two-step process chain for plate materials is a feasible possibility. Cutting and welding can be performed in subsequent steps on the same machine for a highly productive process chain. The electron beam is a tool with high energy conversion efficiency, which is largely independent of the type of metal. Its high power density qualifies the non-vacuum electron beam as an outstanding energy source for the well-known NVEB welding as well as for high-speed cutting. Welding is possible with or without filler wire or shielding gas, depending on the application. The NVEB-cutting process employs a co-moving cutting head with a sliding seal for extremely high cutting speeds producing high quality edges. Due to direct removal of fumes and dust, NVEBC with local suction is an exceptionally clean and fast process. The NVEB welding process is possible directly after cutting, without further edge preparation. The potential directions of development of non-vacuum electron beam technologies are discussed. An exemplary two-step process chain using high-strength steel is presented to highlight possible application in industries such as general steel construction, automotive, shipbuilding, railway vehicle or crane construction. An analysis of the mechanical properties of the resulting weld seam is presented. 展开更多
关键词 WELDING High-Strength Steels non-Vacuum Electron Beam Welding non-Vacuum Electron Beam cutting
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Vegetative propagation of Litsea monopetala, a wild tropical medicinal plant: Effects of indole-3-butyric acid (IBA) on stem cuttings 被引量:12
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作者 Tarit Kumar Baul Mohammad Mosharraf Hossain +1 位作者 Mohammad Mezbahuddin Mohammed Mohiuddin 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第3期409-416,共8页
In this study we investigated the rooting ability and the growth performance of juvenile single-node leafy stem cuttings of Litsea monopetala (Roxb) Pers. collected from two mature mother trees preserved in the hill... In this study we investigated the rooting ability and the growth performance of juvenile single-node leafy stem cuttings of Litsea monopetala (Roxb) Pers. collected from two mature mother trees preserved in the hill forest of Chittagong district, Bangladesh. The rooting ability of cuttings was studied under 0%, 0.1%, 0.2% and 0.4% indole-3-butyric acid (IBA) treatments. Significantly better rooting response (p ≤ 0.05) was observed with 0.1% IBA compared to control (0% IBA). The mean number of roots and the length of the longest root of cuttings in different treatments showed no significant difference (p≤0.05). After transfer into polythene bags from non-mist propagator, rooted cuttings treated with 0%, 0.1% and 0.2% IBA demonstrated the highest (100 ± 0.00%) survival capacity. The mean number of shoots developed in cuttings in the polythene bags in first three weeks varied significantly (p≤0.05) among the treatments. Effects of three fertilizer treatments, viz. T0 (no fertilizer), T1 (10g Urea, 20g TSP, 10g MOP dissolved in 1 L water) and T2 (10g Urea, 20g TSP, 10g MOP dissolved in 2 L water) on initial growth ofstecklings were also measured over a 90-days period. The increment of leaf area of stecklings was significantly higher (p≤0.05) under T0 compared with that under T1 and T2 while the increment of stem length, collar diameter and root biomass varied insignificantly among different fertilizer treatments. The results suggest that rooting juvenile single-node leafy stem cuttings could be an effective mean of regenerating L. monopetala. The application of 0.1% IBA concentration is recommended for rooting of juvenile leafy stem cuttings and application of fertilizer appeared unnecessary for the subsequent growth of stecklings in polythene bags. 展开更多
关键词 IBA Litsea monopetala non-mist propagator ROOTING stem cutting
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Identification and Metabolic Mechanism of Non-fermentative Short-cut Denitrifying Phosphorus-removing Bacteria 被引量:11
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作者 刘晖 孙彦富 +5 位作者 贾晓珊 李军 周康群 屈向东 陶雪琴 陈瑜 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第3期332-340,共9页
To investigate the characteristics and metabolic mechanism of short-cut denitrifying phosphorus-removing bacteria (SDPB) that are capable of enhanced biological phosphorus removal (EBPR) using nitrite as an electron a... To investigate the characteristics and metabolic mechanism of short-cut denitrifying phosphorus-removing bacteria (SDPB) that are capable of enhanced biological phosphorus removal (EBPR) using nitrite as an electron acceptor, an aerobic/anoxic sequencing batch reactor was operated under three phases. An SDPB-strain YC was screened after the sludge enrichment and was identified by morphological, physiological, biochemical properties and 16S rDNA gene sequence analysis. Denitrifying phosphorus-removing experiments were conducted to study anaerobic and anoxic metabolic mechanisms by analyzing the changes of chemical oxygen demand (COD), phosphate, nitrite, poly-β-hydroxybutyrate (PHB), and glycogen. The results show that strain YC is a non-fermentative SDPB similar to Paracoccus denitrificans. As a kind of non-fermentative bacteria, the energy of strain YC was mainly generated from phosphorus release (96.2%) under anaerobic conditions with 0.32 mg P per mg synthesized PHB. Under anoxic conditions, strain YC accumulated 0.45 mg P per mg degraded PHB, which produced most of energy for phosphate accumulation (91.3%) and a little for glycogen synthesis (8.7%). This metabolic mechanism of strain YC is different from that of traditional phosphorus-accumulating organisms (PAOs). It is also found that PHB, a kind of intracellular polymer, plays a very important role in denitrifying and accumulating phosphorus by supplying sufficient energy for phosphorous accumulation and carbon sources for denitrification. Therefore, monitoring ΔP/ΔPHB and ΔNO2--N/ΔPHB is more necessary than monitoring ΔP/ΔCOD,ΔNO2--N/ΔCOD, or ΔP/ΔNO2--N. 展开更多
关键词 反硝化除磷菌 代谢机制 发酵菌 短切 鉴定 强化生物除磷 SBR反应器 生理生化特性
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A Simple Method to Derive Minimal Cut Sets for a Non-coherent Fault Tree 被引量:2
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作者 Takehisa Kohda 《International Journal of Automation and computing》 EI 2006年第2期151-156,共6页
Minimal cut sets (or prime implicants: minimal combinations of basic event conditions leading to system failure) are important information for reliability/safety analysis and design. To obtain minimal cut sets for ... Minimal cut sets (or prime implicants: minimal combinations of basic event conditions leading to system failure) are important information for reliability/safety analysis and design. To obtain minimal cut sets for general non-coherent fault trees, including negative basic events or multi-valued basic events, a special procedure such as the consensus rule must be applied to the results obtained by logical operations for coherent fault trees, which will require more steps and time. This paper proposes a simple method for a non-coherent fault tree, whose top event is represented as an AND combination of monotonic sub-trees. A "monotonic" sub-tree means that it does not have both positive and negative representations for each basic event. It is proven that minimal cut sets can be obtained by a conventional method for coherent fault trees. An illustrative example of a simple event tree analysis shows the detail and characteristics of the proposed method. 展开更多
关键词 non-coherent fault trees monotonic sub-trees minimal cut sets.
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Vegetative propagation of Holarrhena pubescens,a wild tropical medicinal plant:effect of indole-3-butyric acid (IBA) on stem cuttings 被引量:1
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作者 Tarit Kumar BAUL Mohammad MEZBAHUDDIN +1 位作者 Mohammad Mosharraf HOSSAIN Mohammed MOHIUDDIN 《Forestry Studies in China》 CAS 2010年第4期228-235,共8页
The present study investigated the rooting ability and growth performance of juvenile single-node leafy stem cuttings of Holarrhena pubescens, collected from two mature mother trees preserved in the hill forests of Ch... The present study investigated the rooting ability and growth performance of juvenile single-node leafy stem cuttings of Holarrhena pubescens, collected from two mature mother trees preserved in the hill forests of Chittagong District, Bangladesh. The rooting ability of cuttings was studied with 0, 0.1%, 0.2% and 0.4% indole-3-butyric acid (IBA) treatments. The better rooting response was observed with 0.1% IBA, but was insignificant compared to other treatments. The mean number of roots and length of the longest root of cuttings in different treatments showed no significant difference. After transfer to the polythene bags from a nonmist propagator, rooted cuttings treated with 0.4% IBA demonstrated the highest (50.00± 0.78%) survival capacity. Regarding initial growth of established rooted cuttings (stecklings) over a 90 d period, the increment of stem length of stecklings under T2 (10 g Urea, 20 g TSP, 10 g MOP dissolved in 2 L water) and leaf area expansion of stecklings under T1 (10 g Urea, 20 g TSP, 10 g MOP dissolved in 1 L water) was significantly higher (p 〈 0.05) compared with that under TO (no fertilizer). The increment of collar diameter and root biomass production varied insignificantly among different fertilizer concentrations, although stecklings under T2 showed the better performance. The results suggest that rooting juvenile single-node leafy stem cuttings can be an effective mean of regenerating H. pubescens. The application of 0.1% IBA or without IBA is recommended for rooting juvenile leafy stem cuttings. Application of fertilizer appears necessary for subsequent growth of stecklings in polythene bags. 展开更多
关键词 IBA non-mist propagator ROOTING stem cutting stecklings
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Realization of non HF air plasma cutting power source based on a complexisolated inverter
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作者 柳刚 胡绳荪 +1 位作者 范荣焕 孙栋 《China Welding》 EI CAS 1999年第2期33-37,共5页
On the basis of analyzing and testing of common inverting circuits, a new type inverter, which has a special inverting circuit called complex isolated, has been put forward. In turn, an applicable air plasma cutting ... On the basis of analyzing and testing of common inverting circuits, a new type inverter, which has a special inverting circuit called complex isolated, has been put forward. In turn, an applicable air plasma cutting machine has also been put into use. Testing results show that this kind inverter has lots of properties as high reliability, high efficiency, good EMC(electromagnetic compatibility) and easy operating. The complex isolated inverting circuit can be considered as a quite valuable reference for the research of high power welding inverter. 展开更多
关键词 complex isolated inverting circuit air plasma cutting non HF sparking inner drag output characteristics
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Preliminary Study on Water Demand Law of 1-0 Rooted Cuttings of Populus szechuanica
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作者 Dabuqiong Haoyu WANG +2 位作者 Huanhuan XIE Zhen XING Yanhui YE 《Meteorological and Environmental Research》 CAS 2021年第4期39-42,共4页
In order to provide theoretical basis and technical support for the afforestation and artificial water supply of P.szechuanica in arid areas,the characteristics of water consumption of P.szechuanica were explored,and ... In order to provide theoretical basis and technical support for the afforestation and artificial water supply of P.szechuanica in arid areas,the characteristics of water consumption of P.szechuanica were explored,and the law of water demand of P.szechuanica was grasped.In this paper,potted seedlings of 1-0 rooted cuttings of P.szechuanica were taken as research objects,and change situation of water consumption under different water control gradients was measured regularly by using weighing method,further analyzing dynamic change of water consumption of P.szechuanica and revealing water demand law of 1-0 rooted cuttings of P.szechuanica.The results showed that total change of water consumption of 1-0 rooted cuttings of P.szechuanica had"slow-fast-slow-fast"double-peak trend in the growth period of the current year,and corresponded with univariate linear relation(R^(2)=0.7137),with significant difference.In whole growth period,water consumption in August was the highest,which was 2.7 times of that in June and July and 1.5 times of that after September.In different water control treatments,the dynamic changes of daily and monthly water consumption were significantly different.In seven water control treatments,monthly water consumption was between(6315.95±1690.70)and(10105.28±3065.30)g/month,and mean was(8211.07±2308.23)g/month.With intensification of water control treatment,water consumption increased,but there was no seedling death due to water shortage.P.szechuanica has great plasticity in water demand,and can survive in both arid and humid environments.Meanwhile,it is revealed that P.szechuanica is the most widely distributed tree species in the region. 展开更多
关键词 Populus szechuanica 1-0 rooted cuttings Water consumption Water demand law
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A survey of digital paper-cutting 被引量:1
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作者 LEI Hongyuan 《Computer Aided Drafting,Design and Manufacturing》 2012年第3期12-17,共6页
Paper-cutting is one of the most fantastic Chinese folk arts. With the aid of computers, digital paper-cutting has become a popular topic in the field of NPR research. This paper will make a comprehensive survey of re... Paper-cutting is one of the most fantastic Chinese folk arts. With the aid of computers, digital paper-cutting has become a popular topic in the field of NPR research. This paper will make a comprehensive survey of related references in four as- pects-image-based paper-cutting, paper-cutting based on computer graphics, paper architectures and paper-cutting animation and it shows that the imitation of the masters' artistic styles of paper-cutting will be the trend of future study. 展开更多
关键词 PAPER-cutting digital technology non-photorealistic RENDERING THRESHOLDING black and white GRAPHICS
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Cutting and other forms of derma-abuse in adolescents
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作者 Hari D. Maharajh Rainah Seepersad 《Health》 2010年第4期366-375,共10页
Cutting or self inflicted epidermal damage (derma-abuse) describes a number of blood- letting behaviours among adolescents. Unlike suicidal behaviour, it is associated with low lethality and the absence of suicidal at... Cutting or self inflicted epidermal damage (derma-abuse) describes a number of blood- letting behaviours among adolescents. Unlike suicidal behaviour, it is associated with low lethality and the absence of suicidal attempts. The purpose of this study is two-fold: Firstly, to present and discuss vignettes of four young adolescents and secondly, to study the dynamics and characteristics of six derma-abusers who have attended Dual Group Therapy (DGT) concurrently with their parents for a six month period. Our findings suggest that patients involved in derma-abuse are generally non-suicidal but engage in comfort cutting for the psychological release of pain, tension reduction and anger management. There is a preponderance of females (80%) with an over-representation of mixed origin and borderline cultural states. In this small group, males amounted to 20% and were more bizarre, gruesome and brutal in their self-abuse. Of the total sample, 10% were of African origin, 60% were of Indian descent and 30% were of mixed ancestry. Psy- chodynamic factors explored in Dual Group Therapy (DGT) are the emphasis on non-suicidal intent, association with tension reduction, reclaiming power and mastery over self and others, life and death instincts, the significance of bloodletting in a socio-cultural context, trans- generational conflicts, dysfunctional family dynamics frequently with parental separation and sexual abuse and early sexual induction. 展开更多
关键词 Derma-Abuse cutting SELF-HARM Adolescents non-Suicidal INTENT
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肥胖儿童non-HDL-C、remnant cholesterol与亚临床动脉粥样硬化的关系 被引量:4
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作者 焦朝艳 刘戈力 +4 位作者 鲍鹏丽 魏莹 杨箐岩 郑荣秀 赵菁 《天津医科大学学报》 2014年第1期25-28,共4页
目的:了解non-HDL-C和remnant cholesterol与肥胖儿童亚临床动脉粥样硬化(AS)的关系。方法:根据甘油三酯(TG)水平将65例肥胖儿童(肥胖组)分为I组(TG≥2.3 mmol/L)32例,II组(TG<2.3 mmol/L)33例,与肥胖组儿童性别年龄相匹配的正常体... 目的:了解non-HDL-C和remnant cholesterol与肥胖儿童亚临床动脉粥样硬化(AS)的关系。方法:根据甘油三酯(TG)水平将65例肥胖儿童(肥胖组)分为I组(TG≥2.3 mmol/L)32例,II组(TG<2.3 mmol/L)33例,与肥胖组儿童性别年龄相匹配的正常体质量儿童30例为III组(对照组)。比较3组儿童血脂指标,对肥胖组各项血脂指标与血浆致动脉粥样硬化指数(AIP)进行相关性分析,肥胖患儿体质指数、血脂指标与颈动脉内径、内膜-中层厚度(c-IMT)、血流参数进行相关性分析。结果:I组、II组的TG、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、non-HDL-C、remnant cholesterol、AIP均较对照组升高,高密度脂蛋白胆固醇(HDL-C)较对照组降低,且I组的remnant cholesterol、AIP均较II组升高。肥胖组儿童AIP与TG、non-HDL-C、remnant cholesterol呈正相关,与HDL-C呈负相关。37例行颈动脉超声检查的肥胖儿童的c-IMT较正常儿童的增厚。结论:non-HDL-C、remnant cholesterol在肥胖儿童亚临床AS中有重要作用,在肥胖儿童血脂异常的治疗中应关注non-HDL-C、remnant cholesterol的变化。 展开更多
关键词 儿童肥胖 亚临床动脉粥样硬化 non—HDL—C REMNANT CHOLESTEROL 血浆致动脉粥样硬化指数 颈动脉内膜-中层厚度
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基于二维约束Non-Guillotine切割的插补算法 被引量:3
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作者 李友如 阎春平 刘飞 《重庆大学学报(自然科学版)》 EI CAS CSCD 北大核心 2002年第10期43-45,55,共4页
分析了二维约束Non -Guillotine切割问题常用求解算法的特点和不足之处。针对二维切割问题的数学模型 ,提出了一种应用列生成法和模拟退火算法的插补算法 ,通过分析该算法的逻辑结构和数据结构 ,展现它运算处理速度快和所得解的最优、... 分析了二维约束Non -Guillotine切割问题常用求解算法的特点和不足之处。针对二维切割问题的数学模型 ,提出了一种应用列生成法和模拟退火算法的插补算法 ,通过分析该算法的逻辑结构和数据结构 ,展现它运算处理速度快和所得解的最优、性能好的特点。并以依据该算法设计的下料软件系统的生产使用效果进一步反映了该算法的新颖和高效。 展开更多
关键词 二维约束non-Guillotine切割 启发式算法 插补算法 数学模型 列生成法 模拟退火算法
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Layer regrouping for water-flooded commingled reservoirs at a high water-cut stage 被引量:2
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作者 Chuan-Zhi Cui Jian-Peng Xu +3 位作者 Duan-Ping Wang Zhi-Hong Liu Ying-song Huang Zheng-Ling Geng 《Petroleum Science》 SCIE CAS CSCD 2016年第2期272-279,共8页
Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to impro... Layer regrouping is to divide all the layers into several sets of production series according to the physical properties and recovery percent of layers at high water-cut stage, which is an important technique to improve oil recovery for high water-cut multilayered reservoirs. Dif- ferent regroup scenarios may lead to different production performances. Based on unstable oil-water flow theory, a multilayer commingled reservoir simulator is established by modifying the production split method. Taking into account the differences of layer properties, including per- meability, oil viscosity, and remaining oil saturation, the pseudo flow resistance contrast is proposed to serve as a characteristic index of layer regrouping for high water-cut multilayered reservoirs. The production indices of multi- layered reservoirs with different pseudo flow resistances are predicted with the established model in which the data are taken from the Shengtuo Oilfield. Simulation results show that the pseudo flow resistance contrast should be less than 4 when the layer regrouping is implemented. The K-means clustering method, which is based on the objec- tive function, is used to automatically carry out the layer regrouping process according to pseudo flow resistances. The research result is applied to the IV-VI sand groups of the second member of the Shahejie Formation in the Shengtuo Oilfield, a favorable development performance is obtained, and the oil recovery is enhanced by 6.08 %. 展开更多
关键词 Water-flooded reservoirs Layer regrouping.Flow resistance - High water cut Reservoir simulation
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Longwall mining “cutting cantilever beam theory” and 110 mining method in China——The third mining science innovation 被引量:62
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作者 Manchao He Guolong Zhu Zhibiao Guo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第5期483-492,共10页
With the third innovation in science and technology worldwide, China has also experienced thismarvelous progress. Concerning the longwall mining in China, the "masonry beam theory" (MBT) wasfirst proposed in the 1... With the third innovation in science and technology worldwide, China has also experienced thismarvelous progress. Concerning the longwall mining in China, the "masonry beam theory" (MBT) wasfirst proposed in the 1960s, illustrating that the transmission and equilibrium method of overburdenpressure using reserved coal pillar in mined-out areas can be realized. This forms the so-called "121mining method", which lays a solid foundation for development of mining science and technology inChina. The "transfer rock beam theory" (TRBT) proposed in the 1980s gives a further understanding forthe transmission path of stope overburden pressure and pressure distribution in high-stress areas. In thisregard, the advanced 121 mining method was proposed with smaller coal pillar for excavation design,making significant contributions to improvement of the coal recovery rate in that era. In the 21st century,the traditional mining technologies faced great challenges and, under the theoretical developmentspioneered by Profs. Minggao Qian and Zhenqi Song, the "cutting cantilever beam theory" (CCBT) wasproposed in 2008. After that the 110 mining method is formulated subsequently, namely one stope face,after the first mining cycle, needs one advanced gateway excavation, while the other one is automaticallyformed during the last mining cycle without coal pillars left in the mining area. This method can beimplemented using the CCBT by incorporating the key technologies, including the directional presplittingroof cutting, constant resistance and large deformation (CRLD) bolt/anchor supporting systemwith negative Poisson's ratio (NPR) effect material, and remote real-time monitoring technology. TheCCBT and 110 mining method will provide the theoretical and technical basis for the development ofmining industry in China. 展开更多
关键词 Mining innovation 121 mining method cutting cantilever beam theory (CCBT) non-pillar mining 110 mining method
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Principles of the roof cut short-arm beam mining method (110 method) and its mining-induced stress distribution 被引量:11
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作者 Tao Zhigang Song Zhigang +2 位作者 He Manchao Meng Zhigang Pang Shihui 《International Journal of Mining Science and Technology》 EI CSCD 2018年第3期391-396,共6页
Since the 1960 s, mining science and technology in China has experienced two technical innovations, i.e.the ‘‘Masonry Beam Theory(MBT)" and ‘‘Transfer Rock Beam Theory(TRBT)". Based on those theories, th... Since the 1960 s, mining science and technology in China has experienced two technical innovations, i.e.the ‘‘Masonry Beam Theory(MBT)" and ‘‘Transfer Rock Beam Theory(TRBT)". Based on those theories, the conventional mining method(being called the 121 mining method) was established, consisting of excavating two tunnels with a pillar left for mining a working panel. However, with increasing mining depth,engineering geological disasters in the underground caverns have been frequently encountered. In addition, the use of the coal-pillar mining results in a large amount of coal resources unexploited. In order to address the problems above, the ‘‘Roof Cut Short-Arm Beam Theory(RCSBT), being called the 110 mining method)" was proposed by He Manchao in 2008. The 110 mining method features the mining of one coal seam panel, excavating necessarily only one roadway tunnel and leaving no pillars. Realization of the 110 mining method includes the following steps:(1) directional pre-splitting roof cutting,(2) supporting the roof by using high Constant Resistance Large Deformation bolt/cable(CRLD), and(3) blocking gangue by hydraulic props. This paper presents an overview of the principles, techniques and application of the 110 mining method. Special emphasis is placed on the numerical simulation of the geostress distribution found in the mining panel using the 110 method compared to that of the 121 method. In addition, the stress distribution on the ‘‘short beam" left by the roof cutting when performing the 110 method was also investigated using both numerical simulation and theoretical formulation. 展开更多
关键词 采矿方法 房顶 分发 横梁 手臂 压力 技术革新 数字模拟
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Longitudinal waves in one dimensional non-uniform waveguides 被引量:3
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作者 Shuqi Guo,~(1,a) Zhi Zhang,~2 and Shaopu Yang~3 1)Department of Mechanics,Shijiazhuang Tiedao University,Shijiazhuang 050043,China. 2)School of Civil Engineering,Shijiazhuang Tiedao University,Shijiazhuang 050043,China 3)School of Mechanical Engineering,Shijiazhuang Tiedao University,Shijiazhuang 050043,China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第2期33-36,共4页
Wave approach is used to analyze the longitudinal wave motion in one dimensional non-uniform waveguides.With assumptions of constant wave velocity and no wave conversion,there exist four types of non-uniform rods and ... Wave approach is used to analyze the longitudinal wave motion in one dimensional non-uniform waveguides.With assumptions of constant wave velocity and no wave conversion,there exist four types of non-uniform rods and corresponding traveling wave solutions are investigated.The obtained results indicate that the kinetic energy is preserved as a constant and the wave amplitude is inversely proportional to square root of the cross-sectional area of the rod.Under certain condition,there exists a cut-off frequency for the rod with variation in geometric or material properties,below which waves do not propagate along the non-uniform rod.For the rod with arbitrary variable cross-section, the conclusions are similar if the wave frequency is high enough.And a series solution of the wave motion is presented. 展开更多
关键词 longitudinal wave traveling solution cut-off frequency non-uniform rod
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Clonal propagation of Bambusa vulgaris by leafy branch cuttings 被引量:2
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作者 M.S. Islam M.K. Bhuiyan +1 位作者 M. M. Hossain M.A. Hossain 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第3期387-392,共6页
Bambusa vulgaris Schrad ex wendl is a widely cultivated bamboo species in rural Bangladesh for its versatile uses. The vegetative propagation becomes the only viable alternative for this species because B. vulgaris do... Bambusa vulgaris Schrad ex wendl is a widely cultivated bamboo species in rural Bangladesh for its versatile uses. The vegetative propagation becomes the only viable alternative for this species because B. vulgaris does not set seed after sparse flowering, which makes seedling progenies unavailable. A low-cost propagation trial was conducted to explore the clonal propagation techniques for the species with two types of small branch cuttings, nodal leafy cuttings and tip cuttings. The cuttings, after treating with 0, 0.1%, 0.4%, and 0.8% IBA solutions, were kept in non-mist propagator to let them to root for assessing the rooting ability. The cuttings were rooted in four weeks and were allowed to grow in the polybags for 10 months under nursery condition to assess their steckling capacity. The study reveals that both types of branch cuttings are able to develop roots, shoots, to survive and to form rhizome under the nursery condition. Rooting ability of the cuttings was significantly enhanced by the application of rooting hormone - IBA. The highest rooting percentage in nodal leafy cuttings and the tip cuttings (56.67% and 51.0%, respectively) were observed in 0.8% IBA treatment, followed by 0.4% IBA and the lowest (34.3% and 30.0%, respectively) was in control. The highest number of root developed per cutting (9.77 and 8.33 in nodal leafy cuttings and the tip cuttings, respectively) was also obtained from the cuttings treated with 0.8% IBA solution, followed 0.4% IBA treatment and the lowest (3.1 and 2.1, respectively) was in the cuttings without treatment. However, the length of the longest root varied significantly neither with the cutting types nor the concentrations of IBA solution. Survival percentage of the stecklings in nursery condition was significantly enhanced by IBA. 展开更多
关键词 Bambusa vulgaris leafy branch cuttings non-mist propagator rooting ability steckling capacity
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Analysis of Numerical Results in High Temperature Congealment and Chemistry Non-equilibrium Flow Field
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作者 Hong-tao Zheng Zhi-yong Tan +2 位作者 Hai-ou Sun Chun-liang Zhou Zhi-ming Li 《Journal of Marine Science and Application》 2002年第1期26-34,共9页
Using the air plasma ignition technique, physicochemical process of burning can be accelerated; concentration limit ofretrofires both can be extended; reliability of retrofires and stability of burning can be improved... Using the air plasma ignition technique, physicochemical process of burning can be accelerated; concentration limit ofretrofires both can be extended; reliability of retrofires and stability of burning can be improved. In this paper, using internalequivalent heat area in place of electric are that created Ohm heat, the flow fields of thermodynamic equilibrium chemistry con-gealment and chemistry non-equilibrium in the plasma generator were simulated. The influences of the inlet prerotation angleof air, the inlet total pressure of air and the airflow compression angle of spray nozzle on the temperature on the surface of elec- 展开更多
关键词 plasma GENERATOR CHEMISTRY non - EQUILIBRIUM IGNITION technique numerical calculation
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Mathematical model for abrasive suspension jet cutting based on orthogonal test design 被引量:4
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作者 胡贵华 朱文华 +5 位作者 蔡红霞 徐翀 柏余杰 程俊 苑进 俞涛 《Journal of Shanghai University(English Edition)》 CAS 2009年第1期37-44,共8页
This paper describes the application of orthogonal test design coupled with non-linear regression analysis to optimize abrasive suspension jet (AS J) cutting process and construct its cutting model. Orthogonal test ... This paper describes the application of orthogonal test design coupled with non-linear regression analysis to optimize abrasive suspension jet (AS J) cutting process and construct its cutting model. Orthogonal test design is applied to cutting stainless steel. Through range analysis on experiment results, the optimal process conditions for the cutting depth and the kerr ratio of the bottom width to the top width can be determined. In addition, the analysis of ranges and variances are all employed to identify various factors: traverse rate, working pressure, nozzle diameter, standoff distance which denote the importance order of the cutting parameters affecting cutting depth and the kerf ratio of the bottom width to the top width. ~rthermore, non-linear regression analysis is used to establish the mathematical models of the cutting parameters based on the cutting depth and the kerr ratio. Finally, the verification experiments of cutting parameters' effect on cutting performance, which show that optimized cutting parameters and cutting model can significantly improve the prediction of the cutting ability and quality of ASJ. 展开更多
关键词 abrasive suspension jet (AS J) orthogonal test design cutting depth the kerf ratio of the bottom width to the top width non-linear regression analysis verification experiment
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Turbulent Flow Action of Pulp in Wet - Laid Non - Woven Processes
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作者 程隆棣 黄秀宝 于修业 《Journal of China Textile University(English Edition)》 EI CAS 2000年第3期57-59,共3页
The paper deals with the fluid field of web forming in wet-laid non-woven production.The influence of the turbulent flow on blending fiber and occluded fluid produced in pulp flow has been discussed in theory and prac... The paper deals with the fluid field of web forming in wet-laid non-woven production.The influence of the turbulent flow on blending fiber and occluded fluid produced in pulp flow has been discussed in theory and practice.The suitable use of the imported velocity of pulp is very important in producing wet-laid products of good quality. 展开更多
关键词 WET - laid non - woven fiber PULP FLOW TURBULENT FLOW layer FLUID occluded FLUID .
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