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Application of Fuyang Paper Cutting Art in Cultural and Creative Design from the Perspective of Rural Revitalization
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作者 KANG Wenwen 《Journal of Landscape Research》 2024年第3期59-62,共4页
The application significance of Fuyang paper cutting art in cultural and creative design from the perspective of rural revitalization was discussed,and the implementation principles and specific practices of applying ... The application significance of Fuyang paper cutting art in cultural and creative design from the perspective of rural revitalization was discussed,and the implementation principles and specific practices of applying the elements and techniques of Fuyang traditional paper cutting art in cultural and creative products with local features were analyzed to provide reference for rural revitalization and development of cultural industry. 展开更多
关键词 Rural revitalization Fuyang paper cutting Cultural and creative design
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Research on the Resistance of Cutting Mechanism of Mining Longitudinal Roadheader
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作者 Mengjiao NIU Yong ZHAO Yongliang YUAN 《Mechanical Engineering Science》 2024年第1期8-12,共5页
In order to accurately obtain the dynamic characteristics of the cutting mechanism of the mining longitudinal roadheader,combined with the working principle of the mining longitudinal roadheader,the theoretical analys... In order to accurately obtain the dynamic characteristics of the cutting mechanism of the mining longitudinal roadheader,combined with the working principle of the mining longitudinal roadheader,the theoretical analysis and derivation are carried out in detail.By using ADAMS to simulate,the resistance curve and torque curve of the cutting mechanism in different directions are obtained.The results show that ADAMS can effectively predict the excavation resistance and torque of the cutting mechanism of mining longitudinal roadheader,which has certain reference value for future optimization design. 展开更多
关键词 longitudinal roadheader cutting mechanism dynamic characteristics DYNAMICS
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FABRICATION OF DLC COATED COBALT-CEMENTED TUNGSTEN CARBIDE MICRO-DRILLS AND THEIR CUTTING PERFORMANCE 被引量:4
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作者 马玉平 陈明 +1 位作者 向道辉 孙方宏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第2期89-93,共5页
In machining the particle reinforced aluminum based composite material with high Si content using the cobalt-cemented tungsten carbide micro cutting tools, diamond like carbon (DLC) films are deposited on cobalt-cem... In machining the particle reinforced aluminum based composite material with high Si content using the cobalt-cemented tungsten carbide micro cutting tools, diamond like carbon (DLC) films are deposited on cobalt-cemented tungsten carbide micro-drills with two-step pretreatment method. Characteristics of DLC coated tools are investigated in bias-enhanced HFCVD system with the optimized hot filament arrangement. The optimization deposition technology is obtained and the wear mechanism of cutting tools is analyzed. The drilling performance of DLC coated tools is verified by the experiments of cutting particle reinforced aluminum based composite material (Si 15% in volume) compared with uncoated ones. Experimental results show that the two-step pretreatment method is appropriate for complex shaped cemented carbide substrates and ensures the good adhesive strength between the diamond film and the substrate. The cutting performance of DLC coated tool is enhanced 10 times when machining the Si particle reinforced aluminum based metal matrix composite compared with that of uncoated ones under the same cutting conditions. 展开更多
关键词 DLC film bias-enhanced HFCVD cobalt-cemented tungsten carbide cutting tool micro-drilling cutting performance
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Study on the Cutting Rooting of Syriga Microphylla with Tender Branches 被引量:1
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作者 武术杰 周秀华 《Agricultural Science & Technology》 CAS 2010年第11期37-38,81,共3页
[Objective] The study was carried out in order to find out the best method of rapid cutting rooting of Syriga microphylla with tender branches.[Method] Effect of rooting reagent with different concentrations on the ra... [Objective] The study was carried out in order to find out the best method of rapid cutting rooting of Syriga microphylla with tender branches.[Method] Effect of rooting reagent with different concentrations on the rapid cutting rooting of Syriga microphylla with tender branches was studied in our paper.[Result] There was great difference between cuttings with auxin and without auxin.[Conclusion] Tender branches treated by 90 mg/L indole butyric acid(IBA)had the best cutting rooting. 展开更多
关键词 Syriga microphylla Tender branches cutting rooting Rooting reagent
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Effects of Sucrose Concentration and Sunlight on the Cutting of Coleus blumei
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作者 董必慧 曹翔 +3 位作者 李燕 刘岩 王慧 言杰 《Journal of Landscape Research》 2010年第1期51-53,共3页
[Objective] To provide scientific bases for the propagation of Coleus blumei. [Method] With the healthy branches of potted Coleus blumei as experiment materials, effects of sucrose concentration on the rooting of Cole... [Objective] To provide scientific bases for the propagation of Coleus blumei. [Method] With the healthy branches of potted Coleus blumei as experiment materials, effects of sucrose concentration on the rooting of Coleus blumei cuttings as well as effects of sunlight on its growth were studied. [Results] Being compared with the CK (clear water), sucrose solution with low or high concentration will not promote the rooting of Coleus blumei cuttings; illumination will enhance the growth of Coleus blumei cuttings with roots; cutting treatment and management measures will greatly influence the rooting rate of Coleus blumei cuttings. [Conclusions] Sucrose solution will not promote the rooting of Coleus blumei cuttings; illumination will enhance the growth of Coleus blumei cuttings. 展开更多
关键词 COLEUS blumei cutting SUCROSE ILLUMINATION
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Dynamic change of arborous species diversity in natural secondary forests after selective cutting on the north slope of Changbai Mountain, Northeast China
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作者 金永焕 周莉 +3 位作者 谷会岩 代力民 申光日 刘军 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期299-302,共4页
The community characteristics of natural secondary forests on the north slope of Changbai Mountain after selective cutting were investigated, and the dynamics of arborous species diversity during the restoration perio... The community characteristics of natural secondary forests on the north slope of Changbai Mountain after selective cutting were investigated, and the dynamics of arborous species diversity during the restoration period of 28 years were studied. The results showed that the arborous species richness (S) had little change and kept the range of 18-22 all along, the Simpson index (D) of the secondary layer and regeneration layer and whole stand had similar trends of change, but that of the canopy layer descended slowly in initial 15 years and had little change later, and the change of diversity index was not obvious and the Shannon-Wiener index (H? fluctuated in a very small scopes (H±10%). 展开更多
关键词 Arborous species diversity Natural secondary forests Selective cutting Northeast China
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Study on the Influencing Factors and the Root Mechanism in Cutting Process of Prunus humilis(Bge). Sok
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作者 杨秀峰 李凤兰 +2 位作者 孙旭红 佟伟霜 胡宝忠 《Agricultural Science & Technology》 CAS 2009年第2期113-117,共5页
A procedure for cutting Prunus humilis(Bge). Sok was comprehensively studied in this paper. It was found that the key factors involved in this procession were medium, rooting accelerator, concentration of rooting ac... A procedure for cutting Prunus humilis(Bge). Sok was comprehensively studied in this paper. It was found that the key factors involved in this procession were medium, rooting accelerator, concentration of rooting accelerator and type of shoot. The results showed that send was used as mediums; Treatment with 1 000 mg/L AST rooting powder No. 2 and semi-woody shoots were the optimal materials for cutting, and the rooting rate reached 88.1%. Anatomical study on rooting of Prunus hum#is(Bge). Sok cutting has been carded out by the paraffin section method. The observation result shows that the adventitious root primordium of Prunus humili$(Bge). Sok cutting belongs to the type of induced root primordium. The adventitiousroot primordium originates from the cross region of vascular cambium and pith rays. 展开更多
关键词 Prunus humilis(Bge). Sok Green shoot cutting Adventitious roots ANATOMY
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Drag pick cutting tests: A comparison between experimental and theoretical results 被引量:5
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作者 Serdar Yasar Ali Osman Yilmaz 《Journal of Rock Mechanics and Geotechnical Engineering》 CSCD 2018年第5期893-906,共14页
This paper aims at reporting the results of a number of drag pick cutting tests on selected igneous rock samples to compare the experimentally determined maximum cutting force (FC) values with theoreti- cally estima... This paper aims at reporting the results of a number of drag pick cutting tests on selected igneous rock samples to compare the experimentally determined maximum cutting force (FC) values with theoreti- cally estimated ones. First, a review on theoretical rock cutting models proposed for both chisel and conical picks was presented in detail. Experimental study consists of both chisel and conical pick cutting tests in unrelieved (single-pick) cutting mode with varying cutting depths. FC' values were determined from experimental results, and theoretical models were utilized to compute FC for all cutting conditions. Computed and experimentally determined F( data were then compared for a referenced cutting depth. It is shown that the theoretical models might overestimate or underestimate FC' and cannot give reliable results. Finally, explanations for these mismatches were presented. 展开更多
关键词 Rock cutting mechanics Rock cutting tests Vertical rock cutting rig (VRCR) cutting force Rock cutting theories
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Research on the cutting force of a pick 被引量:20
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作者 LIU Song-yong DU Chang-long CUI Xin-xia 《Mining Science and Technology》 EI CAS 2009年第4期514-517,共4页
Cutting tests were done using a test bed designed to measure pick cutting forces when cutting coal and rock.The test equipment has a drum with two starting helical vanes.Cutting forces on a pick were measured as a fun... Cutting tests were done using a test bed designed to measure pick cutting forces when cutting coal and rock.The test equipment has a drum with two starting helical vanes.Cutting forces on a pick were measured as a function of coal compressive strength,pick carbide tip diameter and the cutting depth per drum revolution.The results show that the cutting force is linearly related to the compressive strength.The relationship between the cutting force and both the carbide tip diameter and the cutting depth are exponential.Fluctuation in the cutting force does not increase with coal compressive strength but it has a linear relationship to tip diameter.A plot of cutting force fluctuations versus the cutting depth follows a sigmoidal curve.Based on the analysis of these test results a theoretical basis is supplied for design and effective use of shearer drums. 展开更多
关键词 PICK cutting force SHEARER cutting theory carbide tip diameter cutting depth
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Longwall mining “cutting cantilever beam theory” and 110 mining method in China——The third mining science innovation 被引量:65
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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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Effects of mother tree ages, different rooting mediums, light conditions and auxin treatments on rooting behaviour of Dalbergia sissoo branch cuttings 被引量:13
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作者 Bhupendra Singh Rajendra Yadav B. P. Bhatt 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第1期53-57,共5页
Dalbergia sissoo Roxb. is one of the promising multipurpose tree species of South Asia. Most of the plantations of D. sissoo from seeds are facing severe threats due to the die-back disease, which ultimately causes de... Dalbergia sissoo Roxb. is one of the promising multipurpose tree species of South Asia. Most of the plantations of D. sissoo from seeds are facing severe threats due to the die-back disease, which ultimately causes death of this potential tree-species within a few months. Vegetative propagation could avoid the die-back disease. Thirty mother trees of different age-groups of D. sissoo were selected for evaluating the rooting behaviour of branch cuttings from D. sissoo as influenced by auxins (IAA or IBA at 100, 200, 500 mg·L^-1), ages of mother trees (10, 4 and 2 years old) and different environment conditions, i.e., different mediums (soil and sand) or light conditions (in shade and open condition). The results show that application of IAA and IBA induced more numbers of cuttings (collected from 10-year-old mother trees) to root compared to control. Branch cuttings of D. sissoo collected from 10-year-old mother trees and planted in soil bed in open conditions had 100.0% of cuttings to root in IAA (100 mg·L^-1) and IBA (200 mg·L^-1) treatments. Both rooting medium (Soil and sand) influenced significantly (p〈0.05) on rooting response of branch cuttings. Soil medium was found to achieve maximum no. of branch cuttings to root, compared to sand medium. 展开更多
关键词 Dalbergia sissoo hormonal treatments rooting medium SHADING vegetative propagation branch cutting
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Multiphase Flow and Wear in the Cutting Head of Ultra-high Pressure Abrasive Water Jet 被引量:8
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作者 YANG Minguan WANG Yuli KANG Can YU Feng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期729-734,共6页
Abrasive water jet cutting technology is widely applied in the materials processing today and attracts great attention from scholars, but many phenomena concerned are not well understood, especially in the internal je... Abrasive water jet cutting technology is widely applied in the materials processing today and attracts great attention from scholars, but many phenomena concerned are not well understood, especially in the internal jet flow of the cutting head at the condition of ultra-high pressure. The multiphase flow in the cutting head is numerically simulated to study the abrasive motion mechanism and wear inside the cutting head at the pressure beyond 300 MPa. Visible predictions of the particles trajectories and wear rate in the cutting head are presented. The influences of the abrasive physical properties, size of the jewel orifice and the operating pressure on the trajectories are discussed. Based on the simulation, a wear experiment is carried out under the corresponding pressures. The simulation and experimental results show that the flow in the mixing chamber is composed of the jet core zone and the disturbance zone, both affect the particles trajectories. The mixing efficiency drops with the increase of the abrasive granularity. The abrasive density determines the response of particles to the effects of different flow zones, the abrasive with medium density gives the best general performance. Increasing the operating pressure or using the jewel with a smaller orifice improves the coherency of p articles trajectories but increases the wear rate of the jewel holder at the same time. Walls of the jewel holder, the entrance of the mixing chamber and the convergence part of the mixing tube are subject to wear out. The computational and experimental results give a qualitative consistency which proves that this numerical method can provide a reliable and visible cognition of the flow characteristics of ultra-high pressure abrasive water jet. The investigation is benefit for improving the machining properties of water jet cutting systems and the optimization design of the cutting head. 展开更多
关键词 abrasive water jet cutting head multiphase flow WEAR
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Dynamic Calibration of the Cutting Temperature Sensor of NiCr/NiSi Thin-film Thermocouple 被引量:16
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作者 CUI Yunxian YANG Deshun +2 位作者 JIA Ying ZENG Qiyong SUN Baoyuan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第1期73-77,共5页
In high-speed cutting, natural thermocouple, artificial thermocouple and infrared radiation temperature measurement are usually adopted for measuring cutting temperature, but these methods have difficulty in measuring... In high-speed cutting, natural thermocouple, artificial thermocouple and infrared radiation temperature measurement are usually adopted for measuring cutting temperature, but these methods have difficulty in measuring transient temperature accurately of cutting area on account of low response speed and limited cutting condition. In this paper, NiCr/NiSi thin-film thermocouples(TFTCs) are fabricated according to temperature characteristic of cutting area in high-speed cutting by means of advanced twinned microwave electro cyclotron resonance(MW-ECR) plasma source enhanced radio frequency(RF) reaction non-balance magnetron sputtering technique, and can be used for transient cutting temperature measurement. The time constants of the TFTCs with different thermo-junction film width are measured at four kinds of sampling frequency by using Ultra-CFR short pulsed laser system that established. One-dimensional unsteady heat conduction model is constructed and the dynamic performance is analyzed theoretically. It can be seen from the analysis results that the NiCr/NiSi TFTCs are suitable for measuring transient temperature which varies quickly, the response speed of TFTCs can be obviously improved by reducing the thickness of thin-film, and the area of thermo-junction has little influence on dynamic response time. The dynamic calibration experiments are made on the constructed dynamic calibration system, and the experimental results confirm that sampling frequency should be larger than 50 kHz in dynamic measurement for stable response time, and the shortest response time is 0.042 ms. Measurement methods and devices of cutting heat and cutting temperature measurement are developed and improved by this research, which provide practical methods and instruments in monitoring cutting heat and cutting temperature for research and production in high-speed machining. 展开更多
关键词 thin-film thermocouple cutting temperature sensor dynamic calibration one-dimensional unsteady heat conduction response time
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Research on the Influence of Cutting Condition on the Surface Microstruct ure of Ultra-thin Wall Parts in Ultrasonic Vibration Cutting 被引量:9
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作者 GAO Guo-fu, ZHAO Bo, JIAO Feng, LIU Chuan-shao (Department of Mechanical Engineering, Jiaozuo Institute of Technolog y, Henan 454000, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期69-70,共2页
In many fields of high-tech industry the ultra-t hi n wall parts are employed. In this paper the experiments were carried out to dis cuss the surface microstructure of the camera’s guided drawtube by applying ult ras... In many fields of high-tech industry the ultra-t hi n wall parts are employed. In this paper the experiments were carried out to dis cuss the surface microstructure of the camera’s guided drawtube by applying ult rasonic vibration cutting device to the traditional lathe. The influence rule of the cutting condition on the surface roughness was put forward, which was drawn by comparing the ultrasonic cutting with the common cutting by use of the cemen ted carbide tool and the polycrystalline diamond (PCD) tool. The test results sh owed that the ultrasonic cutting performs better than the common cutting in the same condition. According to the test results analyzing, the surface characteriz ation is influenced clearly by the rigidity of the acoustic system and the machi ne tool, as well the setting height of the tool tip. Otherwise, the dense regula r low frequency vibration ripples will be scraped on the machined surface. When the tool tip is set higher than the rotating center of the work piece by three t imes of the amplitude of ultrasonic vibration, the vibration ripples behave alig ht; they turn light and shade alternatively when the tool tip is lower than the rotating center of the work piece by three times of the amplitude of ultrasonic vibration. According to the test result analyzing, the following conclusions are put forward: 1) The surface roughness in ultrasonic cutting is better than that in common cutting. Under a one third critical cutting velocity, the value of th e surface roughness in ultrasonic cutting rise slightly along with the cutting v elocity, while in common cutting it decreases contrast to the cutting velocity; the curves of the surface roughness in ultrasonic cutting and common cutting see m to be alike, both increase along with the feed rate and the cutting depth, but the value in ultrasonic cutting is smaller in the same condition.2) The influen ce of the coolant on the surface roughness cannot be ignored. The kerosene can b e employed to improve the surface roughness in ultrasonic machining.3) In ultras onic cutting process of aluminum alloy ultra-thin wall work piece, the PCD tool performs better than the cemented carbide tools.4) The vibration ripples result from the not enough rigidity of the acoustic system and the improper setting he ight of the tool tip. The departure of the tool tip from the rotating center of the work piece to some extent causes the vibration ripples on the machined surfa ce. 展开更多
关键词 ultra-thin wall parts ultrasonic cutting PCD t ool microstructure surface roughness
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A Heuristic Algorithm for the Fabric Spreading and Cutting Problem in Apparel Factories 被引量:2
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作者 Xiuqin Shang Dayong Shen +1 位作者 Fei-Yue Wang Timo R. Nyberg 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第4期961-968,共8页
We study the fabric spreading and cutting problem in apparel factories.For the sake of saving the material costs,the cutting requirement should be met exactly without producing additional garment components.For reduci... We study the fabric spreading and cutting problem in apparel factories.For the sake of saving the material costs,the cutting requirement should be met exactly without producing additional garment components.For reducing the production costs,the number of lays that corresponds to the frequency of using the cutting beds should be minimized.We propose an iterated greedy algorithm for solving the fabric spreading and cutting problem.This algorithm contains a constructive procedure and an improving loop.Firstly the constructive procedure creates a set of lays in sequence,and then the improving loop tries to pick each lay from the lay set and rearrange the remaining lays into a smaller lay set.The improving loop will run until it cannot obtain any smaller lay set or the time limit is due.The experiment results on 500 cases show that the proposed algorithm is effective and efficient. 展开更多
关键词 Construction and improvement cutting and PACKING FABRIC SPREADING and cutting HEURISTIC algorithm
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Effects of IBA on the rooting of branch cuttings of Chinese jujube (Zizyphus jujuba Mill.) and changes to nutrients and endogenous hormones 被引量:8
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作者 Fengxia Shao Sen Wang +1 位作者 Wen Huang Zhiming Liu 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第6期1557-1567,共11页
‘Zhongqiusucui’ jujube secondary shoots were treated with 3-indolebutyric acid(IBA) at three concentrations, 500, 1000 and 1500 mg/L. Results show that IBA could significantly enhance rooting and root characteristic... ‘Zhongqiusucui’ jujube secondary shoots were treated with 3-indolebutyric acid(IBA) at three concentrations, 500, 1000 and 1500 mg/L. Results show that IBA could significantly enhance rooting and root characteristics of cuttings and were best with IBA at 1500 mg/L. In the rooting process, the formation of adventitious roots was related to the consumption and accumulation of nutrients(soluble sugars and proteins) and the changes in endogenous hormones in phloem, leaf tips and leaf bases. The rooting of cuttings had a positive correlation with the consumption of soluble sugars during the period of callus formation and with the accumulation of soluble sugars during adventitious root formation and growth. Rooting was positively related to the breakdown of soluble proteins in the phloem when the callus formed, and had a positive correlation with its accumulation during adventitious root formation and growth. Leaf tips and leaf bases showed a reverse trend in changes of soluble protein. However, together with the phloem, leaf tips and leaf bases regulated and controlled the formation and development of adventitious roots. The main activities of soluble proteins exist in the leaf tips as this was the main source of soluble proteins. The relation between rooting and IAA(indole-3-acetic acid) content in phloem was positive and thus a high concentration of IAA could benefit the induction and formation of adventitious roots. However, rooting was negatively related with ABA(abscisic acid) and GA(gibberellic acid) and a high concentration of both could inhibit the induction and formation of adventitious roots. Rooting had a positive correlation with phloem IAA/ABA ratios, and higher ratios could improve rooting. Low concentrations of ZR(zeatin riboside) triggered the induction of adventitious roots, while higher concentrations promoted root growth.Endogenous hormones in leaf tips and bases had an impact on rooting. The activities of endogenous hormones mainly existed in leaf tips because they play a major role in the production and consumption of IAA and its ABA content increased during rooting. The ZR in leaf tips influenced the rooting of cuttings, especially in the callus formation and rooting stage. Leaf tips were the main source of GA. 展开更多
关键词 Chinese jujube Ziziphus jujuba Mill. Rooting of cuttings Soluble sugars Soluble proteins Endogenous hormones
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Adiabatic Shear Mechanisms for the Hard Cutting Process 被引量:5
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作者 YUE Caixu WANG Bo +2 位作者 LIU Xianli FENG Huize CAI Chunbin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第3期592-598,共7页
The most important consequence of adiabatic shear phenomenon is formation of sawtooth chip. Lots of scholars focused on the formation mechanism of sawtooth, and the research often depended on experimental approach. Fo... The most important consequence of adiabatic shear phenomenon is formation of sawtooth chip. Lots of scholars focused on the formation mechanism of sawtooth, and the research often depended on experimental approach. For the present, the mechanism of sawtooth chip formation still remains some ambiguous aspects. This study develops a combined numerical and experimental approach to get deeper understanding of sawtooth chip formation mechanism for Polycrystalline Cubic Boron Nitride(PCBN) tools orthogonal cutting hard steel GCr15. By adopting the Johnson-Cook material constitutive equations, the FEM simulation model established in this research effectively overcomes serious element distortions and cell singularity in high strain domain caused by large material deformation, and the adiabatic shear phenomenon is simulated successfully. Both the formation mechanism and process of sawtooth are simulated. Also, the change features regarding the cutting force as well as its effects on temperature are studied. More specifically, the contact of sawtooth formation frequency with cutting force fluctuation frequency is established. The cutting force and effect of cutting temperature on mechanism of adiabatic shear are investigated. Furthermore, the effects of the cutting condition on sawtooth chip formation are researched. The researching results show that cutting feed has the most important effect on sawtooth chip formation compared with cutting depth and speed. This research contributes a better understanding of mechanism, feature of chip formation in hard turning process, and supplies theoretical basis for the optimization of hard cutting process parameters. 展开更多
关键词 adiabatic shear FEM simulation hard cutting process sawtooth chip
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A Decision-Making Framework Model of Cutting Fluid Selection for Green Manufacturing and the Case Study 被引量:5
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作者 TAN Xian-chun 1, LIU Fei 1, CAO Hua-jun 1, ZHANG Hua 2 (1. The Institute of Manufacturing Engineering, Chongqing University, Chongqing 400044, China 2. School of Manufacturing & Automation, Wuhan University of Science & Technol ogy, Wuhan 430081, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期136-137,共2页
Pursuing the green manufacturing (GM) of products i s very beneficial in the alleviation of environment burdens. In order to reap such benefits, green manufacturing is involved in every aspect of manufacturing proc es... Pursuing the green manufacturing (GM) of products i s very beneficial in the alleviation of environment burdens. In order to reap such benefits, green manufacturing is involved in every aspect of manufacturing proc esses. During the machining process, cutting fluid is one of the main roots of e nvironmental pollution. And how to make an optimal selection for cutting fluid f or GM is an important path to reduce the environmental pollution. The objective factors of decision-making problems in the traditional selection of cutting flu id are usually two: quality and cost. But from the viewpoint of GM, environmenta l impact (E) should be considered together. In this paper, a multi-object d ecision-making model of cutting fluid selection for GM is put forward, in which the objects of Quality (Q), Cost(C) and Environmental impact (E) are considered together. In this model, E means to minimize the environmental impact, Q means to maximize the quality and C means to minimize the cost. Each objective is anal yzed in detail too. A case study on a decision-making problem of cutting fluid selection in a gear hobbing process is analyzed, and the result shows the model is practical. 展开更多
关键词 green manufacturing cutting fluid decision-mak ing model environmental impact
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The type, position and age effect on the cutting reproduction of Picea crassifolia and its rooting mechanism in the Qilian Mountains 被引量:6
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作者 Jianjun Kang Wenzhi Zhao +3 位作者 Ming Zhao Guangyu Li Jiqiang Zhang Zhisheng Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期993-1002,共10页
Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its r... Picea crassifolia Kom, a perennial arbor spe- cies is recognized as one of the most adaptable plants found to date in Qilian Mountains. To explore the cutting reproduction technology of P. crassifolia and reveal its rooting mechanism, cuttings of P. crassifolia with different cutting types (softwood, hardwood and root), positions (top, upper, middle and bottom) and ages (7, 10, 15, 20, 25 year-old) were cultivated in a field experiment. One- year old softwood and hardwood cuttings were collected from 7-, 10-, 15-, 20-, and 25 year-old healthy ortets to analyze the changes from endogenous hormones and organic nutrients. Results indicate that the softwood cut- tings (0.5-1.0 cm in diameter) from upper branches of 15 year-old ortets shows better growth performance by improving rooting indexes, including a significant increasein rooting rate and a decrease in basal rot rate. Concomi- tantly, increasing rooting quantity and root length also increased. It is noteworthy that the high rooting rate of P. crassifolia cuttings due to its ability to accumulate high concentrations of indole-3-acetic acid (IAA) and total carbon (TC) rather than abscisic acid (ABA) and total nitrogen (TN). The rooting rate was mainly regulated by the IAA/ABA and TC/TN ratio. In summary, our results suggest that the softwood cuttings (0.5-1.0 cm in diameter) from upper branches of 15 year-old P. crassifolia can be considered as an effective strategy to improve cutting rooting rate, and the IAA/ABA and TC/TN ratio was one of the main factors limiting the cutting rooting rate of P. crassifolia. 展开更多
关键词 Picea crassifolia Kom TYPE Positionand age effect cutting reproduction Rooting rate HORMONES Organic substances
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Smart Cutting Tools and Smart Machining: Development Approaches, and Their Implementation and Application Perspectives 被引量:8
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作者 Kai Cheng Zhi-Chao Niu +2 位作者 Robin C.Wang Richard Rakowski Richard Bateman 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第5期1162-1176,共15页
Smart machining has tremendous potential and is becoming one of new generation high value precision manufacturing technologies in line with the advance of Industry 4.0 concepts. This paper presents some innovative des... Smart machining has tremendous potential and is becoming one of new generation high value precision manufacturing technologies in line with the advance of Industry 4.0 concepts. This paper presents some innovative design concepts and, in particular, the development of four types of smart cutting tools, including a force-based smart cutting tool, a temperature-based internally-cooled cutting tool, a fast tool servo (FTS) and smart collets for ultra- precision and micro manufacturing purposes. Implemen- tation and application perspectives of these smart cutting tools are explored and discussed particularly for smart machining against a number of industrial application requirements. They are contamination-free machining, machining of tool-wear-prone Si-based infra-red devices and medical applications, high speed micro milling and micro drilling, etc. Furthermore, implementation tech- niques are presented focusing on: (a) plug-and-produce design principle and the associated smart control algo- rithms, (b) piezoelectric film and surface acoustic wave transducers to measure cutting forces in process, (c) critical cutting temperature control in real-time machining, (d) in- process calibration through machining trials, (e) FE-based design and analysis of smart cutting tools, and (f) applica- tion exemplars on adaptive smart machining. 展开更多
关键词 Smart cutting tool Smart machining Fast toolservo (FFS) Precision machining Micro manufacturing Smart tooling
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