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Hybrid Multi-Object Optimization Method for Tapping Center Machines
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作者 Ping-Yueh Chang Fu-I Chou +1 位作者 Po-Yuan Yang Shao-Hsien Chen 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期23-38,共16页
This paper proposes a hybrid multi-object optimization method integrating a uniform design,an adaptive network-based fuzzy inference system(ANFIS),and a multi-objective particle swarm optimizer(MOPSO)to optimize the r... This paper proposes a hybrid multi-object optimization method integrating a uniform design,an adaptive network-based fuzzy inference system(ANFIS),and a multi-objective particle swarm optimizer(MOPSO)to optimize the rigid tapping parameters and minimize the synchronization errors and cycle times of computer numerical control(CNC)machines.First,rigid tapping parameters and uniform(including 41-level and 19-level)layouts were adopted to collect representative data for modeling.Next,ANFIS was used to build the model for the collected 41-level and 19-level uniform layout experiment data.In tapping center machines,the synchronization errors and cycle times are important consid-erations,so these two objects were used to build the ANFIS models.Then,a MOPSO algorithm was used to search for the optimal parameter combinations for the two ANFIS models simultaneously.The experimental results showed that the proposed method obtains suitable parameter values and optimal parameter combinations compared with the nonsystematic method.Additionally,the optimal parameter combination was used to optimize existing CNC tools during the commissioning process.Adjusting the proportional and integral gains of the spindle could improve resistance to deformation during rigid tapping.The posi-tion gain and prefeedback coefficient can reduce the synchronization errors significantly,and the acceleration and deceleration times of the spindle affect both the machining time and synchronization errors.The proposed method can quickly and accurately minimize synchronization errors from 107 to 19.5 pulses as well as the processing time from 3,600 to 3,248 ms;it can also shorten the machining time significantly and reduce simultaneous errors to improve tapping yield,there-by helping factories achieve carbon reduction. 展开更多
关键词 tapping center machine uniform design adaptive network-based fuzzy inference system(ANFIS) multi-objective particle swarm optimizer
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CUTTING FORCES IN HIGH SPEED TAPPING CAST IRON BY TUNGSTEN CARBIDE TAPS 被引量:7
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作者 张晓辉 刘钢 +4 位作者 陈明 胡祖光 励政伟 许辉 祝新发 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2007年第2期94-99,共6页
The engineblock production lines need high speed tapping with tungsten carbide taps. In the tapping process, the machining precision and the tool life of taps are directly influenced by tapping forces. And the paramet... The engineblock production lines need high speed tapping with tungsten carbide taps. In the tapping process, the machining precision and the tool life of taps are directly influenced by tapping forces. And the parameter optimization of tap structures is also correlated with the variation of tapping forces. Therefore, the study of tapping forces is necessary in developing new style taps. Several experiments about some novel carbide taps are performed on a vertical machining center by a Kistler dynamometer system in blind tapping both gray cast iron and ductile cast iron. And the variations of tapping forces are analyzed in tapping-in and tapping-out periods. It indicates that cutting forces hardly vary with the tap wear in tapping cast iron. Contrarily, tapping forces are closely correlated with the holding method. Besides, it also depends on the helix angle, the flute numbers and the plasticity of the work material to some extent. 展开更多
关键词 tungsten carbide tap cast iron high speed tapping tapping force
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Standardized gum tapping techniques to maximize yield from high-value Indian tree,Sterculia urens 被引量:1
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作者 Amol Vasishth Vipan Guleria 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第3期615-619,共5页
Industrial applications of natural gums have been expanding tremendously, so gum collection from trees provides an important livelihood for local dwellers in drought-prone Rajasthan and its surroundings states. Tradit... Industrial applications of natural gums have been expanding tremendously, so gum collection from trees provides an important livelihood for local dwellers in drought-prone Rajasthan and its surroundings states. Traditional gum tapping is crude and unscientific; deep incision, untimely extraction and high concentration of chemicals in gum have affected Sterculia urens species in its natural habitat. In studies 2 years on trees having diameter at breast height 〉40 cm from natural stands to maximize gum collection and standardize the tapping method (bore holes vs. V blazes), tapping season, chemical and concentration, different tapping techniques were tes- ted. For tapping maximum gum was collected using bore hole. Ethephon was better as extraction chemical than sulphuric acid. Bore-hole tapping with a 5-cm hole and ethephon at 300 mg/mL yielded the most gum (135.20 g/ tree). Ethephon at 300 mg/mL yielded the most gum. Ethephon induced gummosis without affecting the health of tree. Tapping seasons also significantly affected the gum yield; the most gum was obtained in April-June. 展开更多
关键词 Bore-hole tapping ETHEPHON Natural gum Sterculia urens tapping
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Effect of tapping tools and date of tapping on Acacia polyacantha gum yield in South Kordofan State, Sudan
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作者 Idris Musa Adam Kamal E.M. Fadl 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第1期117-122,共6页
A study was conducted in South Kordofan, Sudan to determine the effect of tapping, tapping tools and date of tapping on the gum yield of Acacia polyacantha. A two-factor experiment was conducted for two seasons in 200... A study was conducted in South Kordofan, Sudan to determine the effect of tapping, tapping tools and date of tapping on the gum yield of Acacia polyacantha. A two-factor experiment was conducted for two seasons in 2008-2009. One location was used for two seasons and two locations for one season. The first factor (4 levels) was the tools of tapping: Makmak, Farrar, and Sonki, and the control which was not tapped. The second factor (2 levels) was the date of tapping that comprises mid October and mid November. These treatments were arranged in Randomaized Complete Block Design and replicated three times. Gum yield (g/tree and g/ picking) was recorded for five pickings. Economic analysis was done using the partial budget technique. The results showed highly significant (p 〈 0.01) differences on gum yield (g/picking and g/tree). The results indicated that the process of tapping increases gum production by 88.4% and 79.8% compared with un-tapped trees, respectively. The date of tapping has no significant effect on gum yield (g/tree and g/picking) of A. polyacantha. Tapping of the tree with Makmak in mid- November was found to be economically beneficial compared to using the other tools and the control. These results could identify a new source of income for the poor farmers in South Kordofan mainly because of the wild occurrence of Kakamut as a potential gum producing tree species grown naturally in the area. 展开更多
关键词 Acacia polyacantha date of tapping gum yield Kakamut South Kordofan tapping tools
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Ultrasonic-assisted vibration tapping using taps with different coatings 被引量:3
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作者 Chung-chen TSAO Kei-lin KUO 《中国有色金属学会会刊:英文版》 CSCD 2012年第S3期764-768,共5页
A machine vision for assessing and inspecting the ratio of thread areas associated with fixed frequency (FF) and limited tracing frequency (LTF) ultrasonic-assisted vibration was presented using differently coated tap... A machine vision for assessing and inspecting the ratio of thread areas associated with fixed frequency (FF) and limited tracing frequency (LTF) ultrasonic-assisted vibration was presented using differently coated taps after tapping of Ti-6Al-4V alloys.Experimental results indicate that TiAlN Micran taps yield the best tapping quality for different coatings and tapping conditions.TiAlN Micran coated taps with LTF make the largest improvement over traditional tapping (TT),with an average increase of 30.2%. 展开更多
关键词 tapping fixed FREQUENCY limited TRACING FREQUENCY TI-6AL-4V alloys
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Determination of optimum tapping date for gum arabic production in South Kordofan State, Sudan 被引量:2
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作者 Idris Musa Adam Kamal E.M. Fadl 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第4期685-688,共4页
Acacia senegal, the gum arabic producing tree, is the most important tree species for the livelihood of the people in South Kordofan State, Sudan. The objective of this study was to determine the optimum tapping date ... Acacia senegal, the gum arabic producing tree, is the most important tree species for the livelihood of the people in South Kordofan State, Sudan. The objective of this study was to determine the optimum tapping date for gum arabic production in the study area. A randomized complete block design experiment with three replications was conducted at (Mead) area for two continuous growing seasons 2008/2009 - 2009/2010. The treatments comprised six tapping dates (1 Oct, 15 Oct, 1 Nov, 15 Nov, 1 Dec, and 15 Dec). Results ishowed highly significant differences (p 〈 0.001) in gum arabic yield (g/tree) in all pickings and in the total gum yield between the tapping dates. The results also showed that tapping of trees on 15 October and 1 November gave a higher yield compared to the other dates. The highest gum yield of 1086.6 and 661.2 g/tree was recorded on 15 October and 15 November, while the lowest gum yield of 297.9 g/tree was recorded when the trees were tapped on 1 October. The two highest-yield dates of tapping (15 Oct and 1 Nov) are recommended as the best time for tapping for gum arabic production in South Kordofan State. These results can be used to increase gum arabic production and farmer income in South Kordofan State. 展开更多
关键词 gum Arabic date of tapping agroforestry system SouthKordofan SUDAN
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THERMAL-CONDUCTIVITY MEASUREMENTS FOR FILLING MATERIALS FOR SLIDING GATES AND THEIR EFFECTS ON FREE- TAPPING PERFORMANCE OF STEEL LADLE 被引量:1
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作者 Z.H.Jiang 1) ,Y.He 2) ,X.L.Jiang 1) , G.J.Han 1) and S.S.Rui 1) 1) Department of Iron & Steel Metallurgy, School of Material and Metallurgical Science, Northeastern University, Shenyang 110006, China 2) Institute of Metal Research,T 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1999年第5期1125-1129,共5页
The thermal conductivities of different typical species filling materials for sliding gate systems for steel ladles were measured using a hot wire technique, and the relationships between thermal conductivity and te... The thermal conductivities of different typical species filling materials for sliding gate systems for steel ladles were measured using a hot wire technique, and the relationships between thermal conductivity and temperature were regressed. The factors affecting thermal conductivity were analyzed by using variance analysis for a perpendicular experiment. The effects of thermal conductivity on sliding gate free tapping were studied, and it was revealed that decreasing the thermal conductivity of the filling materials is beneficial in enhancing the rate of free tapping for sliding gates. 展开更多
关键词 filling materials thermal conductivity sliding gate free tapping
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Design Research on Drive System of Underwater Tapping Machine 被引量:1
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作者 喻开安 《China Ocean Engineering》 SCIE EI 2009年第1期175-184,共10页
The underwater tapping machine is composed of a center bit, a tapping cutter, a seal box, a main drive box, a boring bar assembly, a envelop, a gear case, a counter and so on. The drive system in underwater tapping ma... The underwater tapping machine is composed of a center bit, a tapping cutter, a seal box, a main drive box, a boring bar assembly, a envelop, a gear case, a counter and so on. The drive system in underwater tapping machine consists of a worm drive, a gear drive system and a screw drive. The worm drive is in the main drive box. The worm is connected with a hydraulic motor and driven by the hydraulic motor. The gear drive system is a combined gear train which is the combinations of the fixed axes and differential gear train in the gear case. On the one hand, by means of the fixed axes gear trains the turn and power of transmission shaft are transferred to the boring bar and the screw rod, causing differential turn between the boring bar and the screw rod. On the other hand, the turns of the boring bar and the screw rod are transferred to the differential gear train. The differential gear train is used to drive a special counter to count axial travel of the boring bar. The screw drive is composed of a feed screw and a nut on the boring bar. There is the differential turn between the boring bar and the feed screw. By means of the nut, the boring bar can feed automatically. With the movement of the sliding gear 7 in the gear case, the designed drive system can also be provided with the ability of fast forward and fast backward movement of the boring bar in its idle motion, resulting in the increase of the tapping efficiency. 展开更多
关键词 underwater tapping machine mechanical drive system axial travel counting device DESIGN
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Theory of higher harmonics imaging in tapping-mode atomic force microscopy 被引量:1
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作者 李渊 钱建强 李英姿 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期213-218,共6页
The periodic impact force induced by tip-sample contact in a tapping mode atomic force microscope (AFM) gives rise to the non-harmonic response of a micro-cantilever. These non-harmonic signals contain the full char... The periodic impact force induced by tip-sample contact in a tapping mode atomic force microscope (AFM) gives rise to the non-harmonic response of a micro-cantilever. These non-harmonic signals contain the full characteristics of tip-sample interaction. A complete theoretical model describing the dynamical behaviour of tip-sample system was developed in this paper. An analytic formula was introduced to describe the relationship between time-varying tip-sample impact force and tip motion. The theoretical analysis and numerical results both show that the timevarying tip-sample impact force can be reconstructed by recording tip motion. This allows for the reconstruction of the characteristics of the tip-sample force, like contact time and maximum contact force. It can also explain the ability of AFM higher harmonics imaging in mapping stiffness and surface energy variations. 展开更多
关键词 tapping mode atomic force microscopy higher harmonics imaging
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Effect of grass density and date of tapping on Acacia senegal gum yield in north kordofan state, Sudan
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作者 Idris M. Adam M. E. Ballal Kamal El. M. Fadl 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第1期169-172,共4页
We conducted a two-factor experiment in randomized complete block design with four replications during 2004 in El Demokeya Forest Reserve and El Himaira Natural Forest, North Kordofan State, Sudan. The objective was t... We conducted a two-factor experiment in randomized complete block design with four replications during 2004 in El Demokeya Forest Reserve and El Himaira Natural Forest, North Kordofan State, Sudan. The objective was to develop an understanding of the ecological effects of under-story vegetation and tapping date on the productivity of gum arabic from Acacia senegal as over story cover. The first factor was grass cover which was tested in four levels (100% and 50% grass cover in addition to bare and burnt). The second factor, date of tapping was tested in three levels namely (1st Oct, 15th Oct and 1st Nov). The first picking was done after 45 days from tapping and the gum yield up to seven pickings was collected at intervals of 15 days. Gum yield from each picking was collected and weighed using sensitive balance. Analysis of variance was carried out using MSTAT-C statistical package, and the Tukey test was applied for mean comparisons. The results showed highly significant differences (p 〈 0.01) of grass cover on gum arabic yield in the two sites for most of the first consecutive pickings (1st–4th out of seven) in addition to total yield (kg/ha). With exception to the 4th pickings, the interaction effect between the grass densities and tapping date was not significantly different. The total gum yield was significantly (p 〈 0.05) increased in only two pickings (third and fourth) in El Demokeya Forest Reserve and two pickings (1st and 2nd) at El Himaira Natural Forest. The density of grass cover significantly (p 〈 0.05) affected the number of pickings at both sites; the number of gum pickings was directly proportional to grass density. The number of gum pickings was found to be significantly (p 〈 0.05) increased at the early date of tapping. 展开更多
关键词 Acacia senegal grass density date of tapping gum arabic yield Sudan.
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Radial growth and non-structural carbohydrate partitioning response to resin tapping of slash pine(Pinus elliottii Engelm.var.elliottii)
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作者 Baoguo Du Qifu Luan +2 位作者 Zhanglin Ni Honggang Sun Jingmin Jiang 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第2期423-433,共11页
Slash pine(Pinus elliottii Engelm.var.elliottii)is a resin-producing species grown worldwide for significant economic benefits for wood production.Resin tapping cre-ates a carbon sink at the expense of carbon allocati... Slash pine(Pinus elliottii Engelm.var.elliottii)is a resin-producing species grown worldwide for significant economic benefits for wood production.Resin tapping cre-ates a carbon sink at the expense of carbon allocation for growth and consequently,wood production may be reduced.Non-structural carbohydrates comprising starch and sugars stored in plant organs,may serve as intermediate pools between assimilation and utilisation.However,the effect of resin tapping between tree growth and non-structural carbo-hydrates is not well understood.This study investigated(1)the effects of resin tapping on radial growth,(2)the effects of resin tapping on non-structural carbohydrate pools in different compartments,and(3)the feasibility of resin pro-duction without disruption of tree growth.Twenty one-year-old slash pines were subjected to resin tapping over two suc-cessive years.Non-structural carbohydrate concentrations in needles,branches,stem phloem,and roots of tapped and untapped trees in summer and winter were determined after the second year of resin harvest.The results showed that tapping had no significant effects on annual increments.Starch was the dominant non-structural carbohydrate frac-tion,regardless of tissues and season,and constituted up to 99%of the total non-structural carbohydrates in the phloem and roots.Glucose and fructose were the dominant sugars;sucrose was negligible.Compared with the controls,tapped trees showed 26%lower non-structural carbohydrate concen-tration in the phloem above the tapping wound in summer,which was attributable to the decreased abundance of starch,glucose,fructose,and sucrose.In winter,the altered non-structural carbohydrate profiles in the phloem above the tap-ping wounding were minimised as a result of recovery of the sugar concentrations.In contrast to free sugars,which accu-mulated substantially in needles and branches during winter,starch was enriched in the phloem,roots,and current-year needles.The results provide evidence for a localised effect of resin tapping,and highlight the observation that resin extrac-tion does not always cause a sacrifice in wood growth under a moderate resin-tapping intensity in slash pine plantations. 展开更多
关键词 Slash pine Localised effects Non-structural carbohydrate Resin tapping Radial growth
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Brief of the technology using sliding gate for slag stopping during converter tapping in the steelmaking plant of Baoshan Iron & Steel Co.,Ltd.
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作者 SUN Xinghong,JIANG Xiaodi and HE Gang Stcelmaking Plant,Baoshan Iron &Steel Co..Ltd.,Shanghai 201900,China 《Baosteel Technical Research》 CAS 2010年第S1期19-,共1页
The sliding gate used to stop slag during converter tapping is similar to the control of slide gate in ladle,with the sliding gate device installed outside the BOF tapping hole tip.Owing to the quick opening and closi... The sliding gate used to stop slag during converter tapping is similar to the control of slide gate in ladle,with the sliding gate device installed outside the BOF tapping hole tip.Owing to the quick opening and closing(in 0.5 s) of the sliding gate,it can not only effectively stop the pre - slag and post - slag during converter tapping but also automatically judge and stop slag with the help of AMEPA slag detecting and PLC control technology.Currently it is regarded as the best process to stop slag during converter tapping. 展开更多
关键词 CONVERTER tapping sliding gate AUTOMATION slag stopping
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Studies on Rubber (<i>Hevea brasiliensis</i>) Trees Exist Plant Type after Planting and Available Tapping Tree of Rubber Plantation in China
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作者 Dongling Qi Jiannan Zhou +1 位作者 Guishui Xie Zhixiang Wu 《American Journal of Plant Sciences》 2014年第20期3017-3021,共5页
Existing plant types of rubber tree after planting and available tapping tree were investigated, and there were about 28 rubber plantations with different tapping years of 8 varieties “CATAS7-33-97”, “CATAS8-79”, ... Existing plant types of rubber tree after planting and available tapping tree were investigated, and there were about 28 rubber plantations with different tapping years of 8 varieties “CATAS7-33-97”, “CATAS8-79”, “CATAS7-20-59”, “PR107”, “RRIM600”, “GT1”, “INA873”, “93-114”in South China. The results showed that there were six kinds of existing plant types of rubber tree after planting of rubber plantations, which were available tapping trees, wind damaged trees, cold damaged trees, tapping panel dryness trees, absent trees and weak trees, respectively. These data investigated also showed rubber trees under available tapping, stoppage due to tapping panel dryness, absence, wind damage, cold damage and weakness were counted and calculated and made up for 72.21%, 14.75%, 5.61%, 3.86%, 2.68% and 1.89%. Tapping panel dryness trees, wind damage and absent trees are major factors for the loss of tapping rubber trees in the rubber plantations. Of these investigated varieties, available tapping trees per 100 trees of rubber plantation of “PR107”at the 1st, 12th, 14th, 16th, 20th, 24th tapping year were 96, 67, 70, 75, 66, 46 trees in Hainan planting zone, respectively. Available tapping trees per 100 trees of rubber plantation of “RRIM600”at the 9th, 15th, 20th, 22nd tapping year were 88, 62, 55, 36 trees in Yunnan planting zone, respectively. Available tapping trees per 100 trees of rubber plantation of “93-114” at the 10th, 19th, tapping year were 94, 62 trees in Guangdong planting zone. These results showed that available tapping trees of rubber plantation decreased with increasing tapping age under different planting zones in China. 展开更多
关键词 RUBBER TREE (Hevea brasiliensis) Exist Plant Type Available tapping TREE RUBBER Plantations Different tapping Years China
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Enhanced clean steel tapping on BOF vessels with the interstop converter gate type CG series
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作者 Benno STEINER Andreas BERGHFER 《Baosteel Technical Research》 CAS 2010年第S1期18-,共1页
Trends in today' s steel production show increasing demands for highly-sophisticated steel grades. Therefore,the steel industry will eventually be required to install best performing technologies to meet governmen... Trends in today' s steel production show increasing demands for highly-sophisticated steel grades. Therefore,the steel industry will eventually be required to install best performing technologies to meet governmental specifications designed to significantly reduce environmental emissions.Such efforts are supported by innovative new solutions in the entire steel making process.One process that will need to be addressed is the cleanliness of the steel in the liquid steel phase,especially during the BOF-tapping process. The new converter gate(CG)(Fig.1) best supports the slide gate tapping technology for converters in terms of clean steel,productivity,yield and availability-at reduced costs. The CG gate introduces a unique feature for converter slide gates:The bottom plate can be exchanged while the gate remains mounted on the converter.This new feature allows for an increased utilisation of the refractory parts and a significant reduction of the downtime of the converter.This 'designed efficiency' is achieved with a refractory set consisting of three identical plates-two bottom plates and one slider plate-and a nozzle.A number of other improvements such as automatic cylinder coupling using the Interstop SNAP technology and a two step tensioning system have also been implemented. The new system is designed to meet minimal space requirements and therefore will adapt to most BOF shops.To perform preparation,service and maintenance work the modular CG gate can be dismounted from the converter and simultaneously replaced by a ready-to-use unit.The degree of automation for dismounting and mounting as well as for off-line preparation has been enhanced and reduces manual efforts. This paper provides a solution to the obvious trend towards efficient and controlled production of clean steel,in general,and especially at BOF shops.Moreover,it specifically describes the operational results of this innovative BOF tapping equipment at Salzgitter Flachstahl GmbH,Germany. 展开更多
关键词 CONVERTER slide gate tapping clean steel REFRACTORY
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Molecular Cloning and Sequence Analysis of an Aquaporin Gene Related to Tapping Panel Dryness in Rubber Tree( Hevea brasiliensis Muell. Arg. )
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作者 Zhi ZOU Yeyong MO +2 位作者 Dahua WANG Feng AN Lifu YANG 《Agricultural Biotechnology》 CAS 2014年第2期37-39,43,共4页
As a syndrome with tapping incision blocked partly or entirely during latex exploiting in rubber tree (Hevea brasiliensis ), "Tapping panel dryness (TPD)" causes great yield losses, thereby becoming the most imp... As a syndrome with tapping incision blocked partly or entirely during latex exploiting in rubber tree (Hevea brasiliensis ), "Tapping panel dryness (TPD)" causes great yield losses, thereby becoming the most important factor limiting rubber production. On the basis of an EST down-regulated in TPD-affected rubber trees, a 903 bp cDNA denoted HbPIP2;2 was isolated from the bark tissue with a combination of in silico cloning and RT-PCR. The cDNA contains an 867 hp ORF, 13 bp 5'UTR and 23 bp 3' UTR. Sequence analysis indicated that HbPIP2;2 encodes 288 amino acids with a theoretical molecular weight (Mw) of 30. 71 kDa and isolectric point (Pi) of 8.20. Bioinformatics analysis suggested that the deduced protein is predicted to have six transmembrane helices located to the plasma membrane and harbor one conserved MIP domain that can be grouped into plasma membrane intrinsic proteins (PIPs) of aquaporin (AQP) family. Homolo- gy search revealed that the protein shares a similarity of more than 90% with the homologues in Ricinus communis, Popttlus trichocarpa, Juglans regia and Theobro- ma cacao, suooorting a hie.hly conserved evolution. This study provided basis for further uncovering the regulatory role of AOPs in TPD occurrence. 展开更多
关键词 Hevea brasiliensis tapping panel dryness AQUAPORIN Plasma membrane intrinsic protein
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Molecular Cloning and Sequence Analysis of a Tonoplast Aquaporin Gene TIP1 Associated with Tapping Panel Dryness in Hevea brasiliensis
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作者 Zhi ZOU Danhua WANG +2 位作者 Yeyong MO Feng AN Lifu YANG 《Agricultural Biotechnology》 CAS 2014年第3期14-17,共4页
[Objective]To address the role of aquaporins(AQPs)in the occurrence of Tapping Panel Dryness(TPD),a phenomenon with tapping incision blocked partly or entirely during latex exploiting in the rubber tree(Hevea bra... [Objective]To address the role of aquaporins(AQPs)in the occurrence of Tapping Panel Dryness(TPD),a phenomenon with tapping incision blocked partly or entirely during latex exploiting in the rubber tree(Hevea brasiliensis)that causes great losses on rubber production,a tonoplast aquaporin gene associated with TPD occurence was cloned and analyzed.[Method]Based on an EST down-regulated in TPD-affected rubber trees,a 774 bp cDNA designated HbTIP1 was isolated from the bark tissue of Hevea brasiliensis with a combination of in silico cloning and RT-PCR.And the gene structure and sequence characteristics were analyzed using bioinformatics tools.[Result]The cDNA includes a 759 bp ORF,8 bp 5’UTR and 7 bp 3’UTR.Sequence analysis indicated that HbTIP1putatively encodes 252 amino acids with a theoretical molecular weight(Mw)of 25.88 kDa and isolectric point(pI)of 4.96.Bioinformatics analysis suggested that the deduced protein is predicted to have six transmembrane helices located to the vacuolar membrane and to harbor one conserved MIP domain that can be grouped into the tonoplast intrinsic proteins(TIPs)of aquaporin family.Homology search revealed that the protein shares a similarity of more than 90%with the homologues in Theobroma cacao,Prunus persica,Citrus sinensis and Ricinus communis,supporting a highly conserved evolution.[Conclusion]This study provided basis for further revealing the regulatory role of AQPs in the TPD occurrence. 展开更多
关键词 Hevea brasiliensis tapping panel dryness AQUAPORIN
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Real Time Recrystallization Study of 1, 2 Dodecanediol on Highly Oriented Pyrolytic Graphite (HOPG) by Tapping Mode Atomic Force Microscopy
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作者 S. K. Dora 《World Journal of Nano Science and Engineering》 2017年第1期1-15,共15页
Real-time atomic force microscopy (AFM) imaging revealed for the first time, the detailed growth/dissolution mechanism of Lauryl glycol (LG) or 1, 2 dodecanediol molecules on HOPG at the nano-level after recrystallizi... Real-time atomic force microscopy (AFM) imaging revealed for the first time, the detailed growth/dissolution mechanism of Lauryl glycol (LG) or 1, 2 dodecanediol molecules on HOPG at the nano-level after recrystallizing them from chloroform solution. At the early stage of recrystallization, parallelogram-like-structures having lengths of several microns and distinct widths (between ~ 100 - 400 nm) were observed. Growth/dissolution behavior of these parallelogram-like-structures as a function of time was investigated. While dissolution occurred along all three dimensions, growth was found to be strictly two dimensional. Both the growth and dissolution process were found to be logarithmic in nature. The average growth rates along their length and width were found to be 11 nm/min and 1.5 nm/min respectively. Average dissolution rate in percentage on HOPG surface was found to be ~ 0.078%/min. Based upon the recrystallization of LG molecules schematics are drawn for a better understanding of the recrystallization process. 展开更多
关键词 1 2 Dodecanediol Kinetics REAL Time Growth tapping Mode AFM
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Identifying Sustainable Practices for Tapping and Sap Collection from Birch Trees: Optimum Timing of Tapping Initiation and the Volume of Nonconductive Wood Associated with Taphole Wounds
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作者 Abby K. van den Berg Mark L. Isselhardt Timothy D. Perkins 《Agricultural Sciences》 2018年第3期237-246,共10页
Experiments were conducted to determine two pieces of information essential to identify practices necessary to ensure tapping trees for birch sap collection is both sustainable and profitable—the selection of the tim... Experiments were conducted to determine two pieces of information essential to identify practices necessary to ensure tapping trees for birch sap collection is both sustainable and profitable—the selection of the time to initiate tapping birch trees to obtain maximum yields, and the volume of nonconductive wood (NCW) associated with taphole wounds in birch trees. The yields obtained from various timing treatments varied between sapflow seasons, but indicate that using test tapholes to choose the appropriate time to initiate tapping is likely to result in optimum yields from birch trees. The volume of NCW associated with taphole wounds in birch trees was highly variable and generally quite large, averaging 220 times the volume of the taphole drilled, and requiring relatively high radial growth rates to maintain NCW at sustainable levels over the long-term. However, more conservative tapping practices, including reduced taphole depth and increased dropline length, as well as thinning and other stand management practices, can be used to reduce the minimum growth rates required. Producers can use this information to ensure that they use tapping practices that will result in sustainable outcomes and obtain the maximum possible sap yields from their trees. 展开更多
关键词 BIRCH SAP BIRCH SYRUP Maple SYRUP tapping COMPARTMENTALIZATION
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Occupational Competencies Required by Secondary School Graduates in Palm Wine Tapping for Sustainable Income in Enugu State, Nigeria
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作者 Asogwa Vincent Mama Romanu Ukonze Juliana 《Journal of Agricultural Science and Technology(B)》 2013年第4期289-295,共7页
The study focused on occupational competencies required by secondary school graduates in palm wine tapping for sustainable income in Enugu State. Four research questions guided the study. Survey research design was ad... The study focused on occupational competencies required by secondary school graduates in palm wine tapping for sustainable income in Enugu State. Four research questions guided the study. Survey research design was adopted. It was carried out in Enugu State. The population for the study was 2,781 registered palm wine tappers. The sample for study was 556 (10%) of palm wine tappers. A random sampling technique was used for the study. A 49 structured competency item questionnaire was used for data collection. Three experts validated the instrument. Cronbach Alphal reliability method was used to determine the internal consistency of the instrument. A reliability coefficient of 0.98 was obtained. 556 copies of the questionnaire were administered to the respondents 541 copies were retrieved and analyzed using mean and standard deviation. The result revealed that 48 competencies were required by secondary school graduates in palm wine tapping occupation for sustainable income in Enugu State. Recommendation was made based on the findings of the study. 展开更多
关键词 Occupational competencies secondary school graduates palm wine tapping.
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A Huge Home Demand Potential Awaits Tapping
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《Contemporary International Relations》 1999年第10期11-14,共4页
Indeed, deficit-spending of massive amounts on public-works, lowering inter-est rates and promoting exports are the common phenomenon seen in today’s post-crisis Asia. But none of them is sustainable, nor a substitut... Indeed, deficit-spending of massive amounts on public-works, lowering inter-est rates and promoting exports are the common phenomenon seen in today’s post-crisis Asia. But none of them is sustainable, nor a substitute for the agonizing re-form, industrial restructuring and sci-tech innovations. The basis for long-term e- 展开更多
关键词 HOME A Huge Home Demand Potential Awaits tapping WILL
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