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插切外齿轮齿形系数的数学模型及影响因素的研究 被引量:1
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作者 周双林 邹慧君 +1 位作者 候慕英 汪萍 《机械设计与研究》 EI CSCD 北大核心 2000年第1期28-30,共3页
本文针对插切加工外齿轮齿形系数研究现状不足 ,利用相对运动原理推导出插切外齿轮齿根过渡曲线和齿形系数的数学模型。讨论插齿刀齿数、变位系数、齿顶圆角半径和相啮合齿轮的齿数、变位系数对插切外齿轮齿形系数的影响 ;同时比较插切... 本文针对插切加工外齿轮齿形系数研究现状不足 ,利用相对运动原理推导出插切外齿轮齿根过渡曲线和齿形系数的数学模型。讨论插齿刀齿数、变位系数、齿顶圆角半径和相啮合齿轮的齿数、变位系数对插切外齿轮齿形系数的影响 ;同时比较插切加工与滚切加工齿轮齿形系数的不同 ,得出插切加工大变位齿轮齿形系数较滚切加工小 ,而对于小变位齿轮则情况相反。因此对于插切加工大变位齿轮有利于提高齿轮弯曲强度。 展开更多
关键词 插切 齿形系数 相对运动 齿根过渡曲线 数字模型
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采用半圆弧刀具超声插切Nomex蜂窝芯的新方法 被引量:1
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作者 康仁科 韩坤 +2 位作者 王毅丹 孟倩 董志刚 《航空制造技术》 2020年第13期14-22,共9页
Nomex蜂窝芯材料具有各向异性、弱刚度的特点,是一种典型的难加工材料。为解决传统插切刀具加工Nomex蜂窝芯时存在的排屑困难、切屑侧的压溃面积大等问题,提出一种采用半圆弧刀具超声插切Nomex蜂窝芯的加工方法。设计了一种新型半圆弧... Nomex蜂窝芯材料具有各向异性、弱刚度的特点,是一种典型的难加工材料。为解决传统插切刀具加工Nomex蜂窝芯时存在的排屑困难、切屑侧的压溃面积大等问题,提出一种采用半圆弧刀具超声插切Nomex蜂窝芯的加工方法。设计了一种新型半圆弧形插切刀具,分析了超声作用下半圆弧形插切刀具的运动规律,揭示了超声振动的引入使切削过程由连续切削变为断续切削的机理。开展了半圆弧刀具超声插切Nomex蜂窝芯的试验,分析了振幅与进给速度对切削力与切削质量的影响规律。试验结果表明,半圆弧刀具超声插切Nomex蜂窝芯可获得良好的加工效果,超声振动的引入可有效降低插切切削力,提高切削表面质量。研究的半圆弧刀具超声插切技术为蜂窝芯零件轮廓边界的高质量加工提供了新的方法。 展开更多
关键词 Nomex蜂窝芯 超声插切 削力 削质量 超声振幅 进给速度
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超声插切Nomex蜂窝芯试验研究
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作者 孙丁一 康仁科 +1 位作者 王毅丹 董志刚 《航空制造技术》 CSCD 北大核心 2021年第17期94-101,共8页
针对Nomex蜂窝芯构件中沿孔格轴向的轮廓边界加工复杂、质量不易控制等问题,在插切加工的基础上提出了一种超声插切的加工方法。开展了超声插切Nomex蜂窝芯试验研究,分别在刀具转速500~1500r/min和进给速度1000~3000mm/min下,进行了传... 针对Nomex蜂窝芯构件中沿孔格轴向的轮廓边界加工复杂、质量不易控制等问题,在插切加工的基础上提出了一种超声插切的加工方法。开展了超声插切Nomex蜂窝芯试验研究,分别在刀具转速500~1500r/min和进给速度1000~3000mm/min下,进行了传统插切与超声插切的切削力测量和切口质量观测试验。试验结果表明,对比传统插切加工,振幅为20μm的超声插切加工在以上加工参数下均能有效降低切削力,平均降幅20%左右;超声插切加工Nomex蜂窝芯切口相对传统插切切口更加平顺、整齐、无毛刺。结合试验结果,进一步分析了刀具与工件在超声插切过程中的相对运动关系和切削力,从理论上解释了超声插切加工中切削力小和插切质量好的原因。 展开更多
关键词 超声插切 Nomex蜂窝芯 插切刀具 削力 表面质量
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插切滚切渐开线齿廓包络线的计算机模拟
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作者 膝献银 高举红 《机械设计》 CSCD 北大核心 1995年第8期11-12,17,共3页
插切滚切渐开线齿廓包络线的计算机模拟膝献银,高举红(天津大学分校)Computersimulationontheslottingandbobbingofinvolutefiankprofiledenvelopecur... 插切滚切渐开线齿廓包络线的计算机模拟膝献银,高举红(天津大学分校)Computersimulationontheslottingandbobbingofinvolutefiankprofiledenvelopecurve¥TeugXianyin;Ga... 展开更多
关键词 齿廓包络线 渐开线 计算机模拟 插切
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用有限元法分析插切外齿轮齿形系数的影响因素
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作者 张志功 高贵梅 +1 位作者 赵建军 刘继先 《新技术新工艺》 2012年第4期95-97,共3页
采用有限元法分析并计算插切加工外齿轮时齿根危险截面位置以及齿形系数。讨论了齿轮的参数以及插齿刀齿数、变位系数和齿顶圆圆角半径对插切外齿轮齿形系数的影响,并绘制了变化曲线,为齿轮的设计和计算提供了一定的参考。
关键词 齿形系数 有限元法 插切加工
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弥勒苣苔叶插繁殖试验研究
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作者 张应祥 《云南农业》 2024年第4期83-85,共3页
为探索珍稀濒危植物弥勒苣苔繁殖方法,开展以无菌种子萌发组培苗叶片切割扦插试验,研究不同叶片切割处理方式对子株数量的影响,找寻最佳繁殖方式,实现规模生产,使之成为唇柱苣苔属和报春苣苔属植物最佳商业化快速繁殖方式。试验结果表明... 为探索珍稀濒危植物弥勒苣苔繁殖方法,开展以无菌种子萌发组培苗叶片切割扦插试验,研究不同叶片切割处理方式对子株数量的影响,找寻最佳繁殖方式,实现规模生产,使之成为唇柱苣苔属和报春苣苔属植物最佳商业化快速繁殖方式。试验结果表明,不带叶柄叶片上段扦插生根和子株出土所需时间均短于带叶柄叶片下段扦插或全叶扦插,不带叶柄有利于生根和出苗。扦插繁殖以叶片切段为好,根据叶片长短可用两段式切段或三段式切段扦插,每段5 cm左右,可得到最佳扦插结果。试验结果说明弥勒苣苔繁殖采用两段式叶片切割扦插或三段式叶片切割扦插繁殖系数最高,扦插苗质量最佳。 展开更多
关键词 弥勒苣苔 全叶扦 段扦 基质 繁殖系数
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富贵竹同一枝条不同切段扦插生根能力的比较(简报) 被引量:10
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作者 陈蔚辉 《植物生理学通讯》 CSCD 1996年第3期182-184,共3页
同一富贵竹枝条,其基部切段扦插的成活率、生根率和生根量大于中部和上部的切段。插条生根率与成活率、生根量均存在极显著相关(r≈0.9)。La(NO3)3和2,4-D对插条生根有明显的促进作用,La(NO3)3对上部切段插条不定根的诱导效... 同一富贵竹枝条,其基部切段扦插的成活率、生根率和生根量大于中部和上部的切段。插条生根率与成活率、生根量均存在极显著相关(r≈0.9)。La(NO3)3和2,4-D对插条生根有明显的促进作用,La(NO3)3对上部切段插条不定根的诱导效果较2,4-D显著。 展开更多
关键词 富贵竹 石蒜科 枝条段扦 生根能力
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冬春季温室切段扦插快繁马铃薯脱毒苗 被引量:1
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作者 高彦萍 杨谋 +4 位作者 李掌 柳永强 齐恩芳 张荣 张武 《长江蔬菜》 2012年第20期18-20,共3页
在近几年试验研究的基础上,提出冬春季温室切段扦插快繁马铃薯脱毒苗模式。试验结果表明,温室温度25~28℃,相对湿度90%,光照5000~10000lx,脱毒苗切段长2.5~3cm,蘸生根液NAA20mg/L+KT2mg/L+GA30.5m∥L,扦插密度1000。130... 在近几年试验研究的基础上,提出冬春季温室切段扦插快繁马铃薯脱毒苗模式。试验结果表明,温室温度25~28℃,相对湿度90%,光照5000~10000lx,脱毒苗切段长2.5~3cm,蘸生根液NAA20mg/L+KT2mg/L+GA30.5m∥L,扦插密度1000。1300株,m。,扦插后喷雾生长调节液(NAA5mg/L+6-BA0.5mg/L+GA31mg/L)和1/2MS营养液或1,2K5营养液+植物叶面肥,20—35d后,苗高8~10cm、茎节6—7个时,进行继代切段繁殖,如此重复继代切段繁殖3-4次,脱毒苗增殖20~25倍。 展开更多
关键词 马铃薯 段扦 快繁 脱毒苗
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温室切段扦插快繁马铃薯脱毒苗的条件及成本分析 被引量:1
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作者 张一帆 安兴旺 《现代农业科技》 2014年第23期128-128,共1页
目前,利用切段扦插方式在温室提高增殖倍数扩繁马铃薯脱毒苗在生产实际中被广泛采用,一方面大幅度降低了马铃薯脱毒苗的生产成本,另一方面基本能保证脱毒苗的质量,使优质、低成本工厂化生产马铃薯脱毒苗变得切实可行。本文总结了温室切... 目前,利用切段扦插方式在温室提高增殖倍数扩繁马铃薯脱毒苗在生产实际中被广泛采用,一方面大幅度降低了马铃薯脱毒苗的生产成本,另一方面基本能保证脱毒苗的质量,使优质、低成本工厂化生产马铃薯脱毒苗变得切实可行。本文总结了温室切段扦插快繁马铃薯脱毒苗的基本条件,从技术层面的更新上提出了降低生产成本的有效措施,并对切段扦插快繁马铃薯脱毒苗的成本进行分析,具有一定的现实参考价值。 展开更多
关键词 马铃薯 脱毒苗 段扦 成本分析
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马铃薯脱毒苗不同茎段扦插苗生产原原种效果研究初报 被引量:3
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作者 龙国 张绍荣 +2 位作者 梅艳 蔡向西 曹曦 《种子》 CSCD 北大核心 2008年第7期75-76,共2页
马铃薯试管苗移栽母苗剪茎扦插,是扩大脱毒原原种生产的有效措施,但从茎尖开始往下剪取不同茎段作扦插材料生产原原种效果有明显差异。本研究以3个不同茎段(每个茎段带2个腋芽)作试验材料,设地、盘栽两组试验,研究不同茎段扦插生产原原... 马铃薯试管苗移栽母苗剪茎扦插,是扩大脱毒原原种生产的有效措施,但从茎尖开始往下剪取不同茎段作扦插材料生产原原种效果有明显差异。本研究以3个不同茎段(每个茎段带2个腋芽)作试验材料,设地、盘栽两组试验,研究不同茎段扦插生产原原种的效果差异。结果表明,马铃薯脱毒苗不同茎段扦插生产原原种以第一茎段效果最好,第二茎段次之,第三茎段较差。 展开更多
关键词 马铃薯脱毒苗 段扦 原原种 粒数 重量
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Research on the Vase Preservative of Anthurium seherzerianum Cut Flowers 被引量:7
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作者 麦有专 李海滨 +3 位作者 温艺超 李炳武 李善志 雷禄旺 《Agricultural Science & Technology》 CAS 2010年第3期151-155,共5页
[Objective] The research aimed to study the vase preservative of Anthurium seherzerianum cut flowers and provide reference for the planting and preservative method selection of A.seherzerianum.[Method] Using Tropical... [Objective] The research aimed to study the vase preservative of Anthurium seherzerianum cut flowers and provide reference for the planting and preservative method selection of A.seherzerianum.[Method] Using Tropical's spathe,one kind of common cut blossoms of A.seherzerianum as experimental materials,three different formula of vase solutions were used.And it was compared with common preservative formula of A.seherzerianum to study the vase preserved liquid of A.seherzerianum.[Result] Formula 3 was the optimum vase preservative,which was composed of 4% sucrose,0.08% NaCl,0.01% Ca(H2PO4)2·H2O,0.01% Chinese medicine antiseptic (ethonal extract from coptis),0.1 mol/L NaOH,0.1 mol/L citric acid and 10 mg/L 6-BA.The preserved period reached 23 days,13 days longer than CK.The appreciative period reached 31 days,18 days longer than CK,with significant effects.In formula 3,water loss in A.seherzerianum spathe was decreased obviously,which was favorable for maintaining water content in tissues.The cell membrane permeability was reduced and the peroxidation of membrane ester was inhibited.The accumulation of MDA was decreased and SOD activity was increased.The protective enzyme activity of cells was enhanced and the content of proline and soluble sugar were increased and the respiration rate was reduced.[Conclusion] The formula(4% sucrose + 0.08% NaCl+ 0.01% Ca(H2PO4)2+0.01% Chinese medicine antiseptic(ethonal extract from coptis)+ 0.1 mol/L NaOH+0.1 mol/L citric acid and 10 mg/L 6-BA)achieved the purpose of prolonging the preservative period of A.seherzerianum spathe and prolonging the preservative period of A.seherzerianum effectively. 展开更多
关键词 Anthurium seherzerianum Cut flowers VASE Preservative period
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Three-dimensional orebody modelling and intellectualized longwall mining for stratiform bauxite deposits 被引量:4
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作者 王少锋 李夕兵 +4 位作者 王善勇 李启月 陈冲 冯帆 陈英 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第10期2724-2730,共7页
Acoupled biharmonic spline and linear interpolation algorithm was proposed to create a three-dimensional smooth deposit model with minimal curvature containing grade and position data. To obtain the optimal technical ... Acoupled biharmonic spline and linear interpolation algorithm was proposed to create a three-dimensional smooth deposit model with minimal curvature containing grade and position data. To obtain the optimal technical parameters, such as cuttingheight and drum diameter, a virtual longwall mining procedure was modelled by simulating the actual fully mechanized longwall mining process. Based on the above work, a bauxite deposit in a longwall mining panel was modelled by scattered grade data from ores sampled on the entry wall. The deposit was then demarcated by industrial indexes and sliced according to the virtual longwallmining procedure. The results show that the proposed interpolation algorithm can depict the stratiform structure of bauxite depositsand that the uncovered bauxite deposit has high proportions of high-grade and rich ore. The ranges of optimal cutting height and drum diameters are 1.72-2.84 m and 1.42-1.72 m, respectively. Finally, an intellectualized longwall mining procedure was designed to guide the mining process with the lowest dilution and loss rates. 展开更多
关键词 stratiform bauxite deposit orebodymodelling interpolation algorithm virtual longwall mining cutting height drum diameter
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马铃薯脱毒苗繁殖方法 被引量:3
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作者 林世君 张丽忱 《农业与技术》 2001年第3期26-27,共2页
关键词 马铃薯 脱毒苗 培养基段扦 土床段扦 嫩尖扦 掰芽育苗
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Submental tracheal intubation for resection of recurrent giant pituitary tumor:a case report
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作者 Zhong Hejiang Wang Yunling Yang Tiande 《Journal of Medical Colleges of PLA(China)》 CAS 2011年第1期40-44,共5页
Airway management in the patients who receive transmaxillary approach for resection of giant pituitary tumor presents a clinical challenge to the anesthesiologists. Oral or nasal route for tracheal intubation can inte... Airway management in the patients who receive transmaxillary approach for resection of giant pituitary tumor presents a clinical challenge to the anesthesiologists. Oral or nasal route for tracheal intubation can interfere with surgical procedures. This report describes submental tracheal intubation for airway management in a patient who underwent resection of recurrent giant pituitary tumor via transmaxillary approach. Submental tracheal intubation is an adaptable and safe alternative technology for airway management during operation. 展开更多
关键词 Submental tracheal intubation Airway management Giant pituitary tumor
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New precut sphincterotomy for endoscopic retrograde cholangiopancreatography in difficult biliary duct cannulation 被引量:20
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作者 Deng-Hao Deng Hong-Nei Zuo Jia-Feng Wang Zhi-E Gu Hong Chen Yuan Luo Ming Chen Wen-Nuo Huang Lu Wang Wei Lu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第32期4385-4390,共6页
AIM: To retrospectively investigate the effect and safety of various new type precut sphincterotomy techniques (VNTPST) in endoscopic retrograde cholangiopancreatography (ERCP) due to difficult biliary duct cannu... AIM: To retrospectively investigate the effect and safety of various new type precut sphincterotomy techniques (VNTPST) in endoscopic retrograde cholangiopancreatography (ERCP) due to difficult biliary duct cannulation (DBC). METHODS: A plough-like pull-type sphincterotome (PLPTS) or improved short nose sphincterotome or improved needle knife was applied. VNTPST was carried out in 30 of 280 patients, whose biliary tract could not be exposed well or deep cannulation was difficult to perform during ERCP with traditional methods. Patients were followed up for short-term complications and the therapeutic effect of VNTPS was observed and compared with that of traditional endoscopic sphincterotomy (EST). RESULTS: A total 280 patients underwent ERCP, of which 3 failed in operation because of pathological features in stomch or duodenum, 247 successfully underwent traditional ERCP (89.1%, 247/277), 30 failed (10.8%, 30/277). VNTPS technique succeeded in 24 (80%, 24/30) of 30 cases. The successful rate of deep biliary duct cannulation increased 8.6% (24/277), the total cannulation successful rate following precut was 97.7%. There was a significant difference between the two groups (97.7% vs 89.1%, x^2= 17.1, P 〈 0.01). The incidence of complications was 9.3% (26/277) for traditional ERCP group and 13.3% (4/30) for VNTPS technique group. Guideline tip was broken in pancreatic duct (KPDGP) of one patient, and there was no pancreatitis, slight or moderate bleeding postoperatively occurred in 2 patients, 1 patient had bleeding during operation (PDWN). There were no differences between VNTPS technique group and traditional ERCP(TRERCP)group (13.3% vs 9.3%, %2 = 0.478, P 〉 0.05). CONCLUSION: VNTPS procedure and Deng's precut are highly effective methods to get biliary access during ERCP with DBC. With skillful techniques, it can increase the successful rate for deep cannulation of biliary duct and decrease complications. VNTPS technique, especially Deng's precut is as effective and safe as EST. This technique can be well performed in hospitals without particular equipments. 展开更多
关键词 endoscopic VNTPST sphincterotomy endoscopic retrograde
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Comparison of early pre-cutting vs standard technique for biliary cannulation in endoscopic retrograde cholangiopancreatography: A personal experience 被引量:4
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作者 Kannikar Laohavichitra Thawatchai Akaraviputh +2 位作者 Asada Methasate Somchai Leelakusolvong Udom Kachintorn 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第27期3734-3737,共4页
AIM: To compare the results and complications of early pre-cutting technique with standard technique. METHODS: From January 2003 to December 2004, a total of 426 consecutive therapeutic biliary ERCP procedures were ... AIM: To compare the results and complications of early pre-cutting technique with standard technique. METHODS: From January 2003 to December 2004, a total of 426 consecutive therapeutic biliary ERCP procedures were performed by one endoscopist (T.A.). Data were retrospectively collected according to procedure indication and results. Of these, 293 procedures (70.4%) were done with standard technique (group A) and 223 procedures (29.6%) with early pre-cutting technique in case of difficult cannulation (group B). The results and complications of ERCP were compared. RESULTS: Success rate of first attempt cannulation was 98.0% in group A and 87.8% in group 13. The overall incidence of post-ERCP pancreatitis, hemorrhage, perforation and cholangitis was 0%, 0.2%, 0.5% and 0.5%, respectively. Morbidity rate was not significantly different. No procedure-related mortality was occurred. CONCLUSION: For an experienced hand, the early pre-cutting technique for biliary cannulation is safe and effective as standard technique. 展开更多
关键词 Pre-cutting Endoscopic retrograde cholan giopancreatography Biliary cannulation COMPLICATION PANCREATITIS
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子长县马铃薯脱毒种薯快速繁育的基本经验
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作者 张小莉 强维荣 +1 位作者 杨光明 营士弘 《中国马铃薯》 2003年第1期45-45,共1页
关键词 子长县 马铃薯 脱毒辣种薯 快速繁育 组织培养 试管苗 段扦
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电生功能水对鲜切月季的保鲜效果研究 被引量:4
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作者 夏丹萍 刘海杰 李里特 《中国农业大学学报》 CAS CSCD 北大核心 2009年第1期93-98,共6页
针对延长切花瓶插寿命的问题,使用几种电生功能水:酸性离子水(EOW,pH=2.5±0.3,ORP=(1125±10)mV,有效氯含量为(50.35±5.00)mg/L)、碱性离子水(ERW,pH=13±0.5,ORP=(-874±5)mV)和对照蒸馏水作为瓶插液对月季切花... 针对延长切花瓶插寿命的问题,使用几种电生功能水:酸性离子水(EOW,pH=2.5±0.3,ORP=(1125±10)mV,有效氯含量为(50.35±5.00)mg/L)、碱性离子水(ERW,pH=13±0.5,ORP=(-874±5)mV)和对照蒸馏水作为瓶插液对月季切花进行保鲜实验。结果表明:电生功能水作为瓶插液用于鲜切月季的保鲜具有良好的效果,酸性水的效果比较明显,5个品种切花月季的瓶插寿命平均延长17.5%的瓶插时间;碱性离子水的保鲜效果稍次,平均切花寿命延长10.1%。实验证明酸碱酸性离子水具保鲜效果,可以作为切花月季延长花期的安全无害的保鲜剂液使用;上述2种电生功能水可以抑制月季切花的蓝变、褐变。 展开更多
关键词 电生功能水 酸性离子水 碱性离子水 月季 花瓶 延长花期 保鲜
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Multivariate Vector Valued Salzer's Theorem 被引量:3
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作者 陈之兵 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2003年第2期233-236,共4页
In this paper, the important Salzer's theorem for rational interpolation is generalized to the multivariate vector valued case.
关键词 MULTIVARIABLE rational interpolation Salzer's theorem.
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TIME-OPTIMAL INTERPOLATION FOR CNC MACHINING ALONG CURVED TOOL PATHES WITH CONFINED CHORD ERROR 被引量:4
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作者 YUAN Chunming ZHANG Ke FAN Wei 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2013年第5期836-870,共35页
In this paper, two new interpolation algorithms lot CNC machining along curve^l tom pathes are proposed: a time-optimal interpolation algorithm under chord error, feedrate, and tangential acceleration bounds, and a g... In this paper, two new interpolation algorithms lot CNC machining along curve^l tom pathes are proposed: a time-optimal interpolation algorithm under chord error, feedrate, and tangential acceleration bounds, and a greedy interpolation algorithm under the chord error and tangential jerk bounds. The key idea is to reduce the chord error bound to a centripetal acceleration bound which leads to a velocity limit curve, called the chord error velocity limit curve. Then, the velocity planning is to find the proper velocity curve governed by the acceleration or jerk bounds '~under" the chord error velocity limit curve. For two types of simple tool pathes, explicit formulas for the velocity curve are given and the methods are implemented in commercial CNC controllers. 展开更多
关键词 Chord error CNC interpolation cubic PH curve JERK quadratic B-spline time-optimalvelocity planning velocity limit curve.
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