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碗状钻头在松散地层中叉孔的应用
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作者 程志忠 石德洲 《中国煤田地质》 2004年第2期55-56,共2页
采用粗径岩心管、水泥封闭等方法在新生界松散层中人为叉孔有时效果不太明显。而碗状钻头人为叉孔成功率高,施工工艺简单,节省了时间,降低了成本。本文结合实例简介了碗状钻头的适用范围。
关键词 碗状钻头 松散地层 叉孔 应用
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变速箱上盖拨叉孔的工艺设计
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作者 张体军 王波 《江苏农机化》 2014年第2期27-29,共3页
通过对变速箱上盖断续拨叉孔结构工艺的分析,提出钻、扩、铰的加工工艺设计方案。
关键词 变速箱 上盖 叉孔 工艺 设计
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在车床上高效率加工变速箱拨叉孔
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作者 李荣海 《金属加工(冷加工)》 2009年第4期28-30,共3页
在机械加工中,要根据本企业现有设备的实际情况,最大限度地发挥现有设备功能,提高设备的利用率,减少设备资金的投入,从而降低制造成本。用改进的车床加工变速箱拨叉孔就能达到这个目的。
关键词 机械加工 车床加工 变速箱 设备功能 制造成本 利用率 叉孔
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SWC型整体叉头十字轴式万向联轴器的装配 被引量:1
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作者 刘体龙 冀银山 +1 位作者 杨富贵 赵宝平 《煤矿机械》 北大核心 2001年第10期40-41,共2页
根据十字轴式万向联轴器的结构特点 ,就万向节与轴叉孔的装配进行了分析 ,设计了一种辅助工装 ,改进了装配方法 。
关键词 万向节 叉孔 装配方法 装配精度 十式轴式万向联轴器
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中国硬孔菌属研究小记及一新记录种(英文) 被引量:1
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作者 李冠华 魏玉莲 《广西植物》 CAS CSCD 北大核心 2011年第1期11-13,共3页
总结了我国硬孔菌属的种类。目前该属在我国共发现11种,其中叉囊硬孔菌为中国新记录种。文中对该种进行了详细描述和显微结构绘图,并给出了该属的检索表。
关键词 囊硬 木生 分类
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污叉丝孔菌菌丝体培养物中烷基苷类化合物(英文) 被引量:4
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作者 谢海辉 徐新亚 +1 位作者 丹阳 魏孝义 《中国天然药物》 SCIE CAS CSCD 北大核心 2009年第5期390-393,共4页
目的:研究污叉丝孔菌Dichomitus squalens(Karst) Reid菌丝培养物中的化学成分。方法:在广东省鼎湖山采集污叉丝孔菌子实体,通过组织培养分离获得菌丝体,然后用多个含有YMG培养基和小麦的10.5L三角瓶进行培养。菌丝体培养物用乙醇提取... 目的:研究污叉丝孔菌Dichomitus squalens(Karst) Reid菌丝培养物中的化学成分。方法:在广东省鼎湖山采集污叉丝孔菌子实体,通过组织培养分离获得菌丝体,然后用多个含有YMG培养基和小麦的10.5L三角瓶进行培养。菌丝体培养物用乙醇提取和溶剂分部,正丁醇溶解部位经柱层析和高效液相色谱分离纯化,用光谱分析法鉴定化合物结构。结果:分离获得了9个化合物,分别鉴定为乙基β-D-吡喃木糖苷(1),乙基β-D-吡喃木糖(1→4)-β-D-吡喃木糖苷(2),正丁基β-D-吡喃木糖苷(3),正丁基β-D-吡喃木糖(1→4)-β-D-吡喃木糖苷(4),乙基β-D-吡喃葡萄糖苷(5),乙基α-L-呋喃阿拉伯糖苷(6),正丁基α-L-呋喃阿拉伯糖苷(7),2-去氧-D-核糖-1,4-内酯(8),2-去氧-D-核酸甲酯(9)。结论:以上化合物系首次从污叉丝孔菌菌丝体培养物中分离获得。 展开更多
关键词 菌丝体培养物 乙基苷 丁基苷
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Volumetric extraction of porous materials based on octree algorithm
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作者 罗守华 李光 顾宁 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期537-540,共4页
Through the octree data structure analysis,a volumetric dataset of closed-cell porous materials is converted into a dataset of hierarchical octree nodes,and then the specific traversal search algorithm on the octree n... Through the octree data structure analysis,a volumetric dataset of closed-cell porous materials is converted into a dataset of hierarchical octree nodes,and then the specific traversal search algorithm on the octree nodes is depicted in details,which is involved in six steps of the volume growth model and one step of the volume decomposition model.Moreover,the conditions of both the proceeding traversal and three possibilities of terminating are given,and the traversal algorithm of completeness is proved from a theoretical perspective.Finally,using a simulated volumetric dataset of columnar pores,the extracting effectiveness of the octree traversal algorithm is verified.The results show that the volume and the distribution information of pores can be successfully extracted by the proposed algorithm,which builds a solid foundation for a more effective performance analysis of porous materials. 展开更多
关键词 OCTREE closed-cell porous materials volume of pores traversal algorithm
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井筒地面预注浆施工方案的探讨
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作者 付杰 马彩霞 《邯郸职业技术学院学报》 2006年第1期49-50,共2页
主要结合施工实例探讨地面预注浆的施工方案,共介绍四种类型:直孔施工、直孔+“S”型孔施工、直孔+叉孔+“S”型孔施工、直孔+“S”型孔+叉孔施工,以及各类施工方案的技术特点。
关键词 地面预注浆 综合注浆 叉孔 “S”型
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Incompressible Pairwise Incompressible Surfaces in Knot Exteriors
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作者 韩友发 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期47-53,共7页
We discuss the properties of incompressible pairwise incompressible surfaces in a knot complement by using twist crossing number. Let K be a pretzel knot or rational knot that its twistindex is less than 6, and l... We discuss the properties of incompressible pairwise incompressible surfaces in a knot complement by using twist crossing number. Let K be a pretzel knot or rational knot that its twistindex is less than 6, and let F be an incompressible pairwise incompressible surface in S 3-K. Then F is a punctured sphere. 展开更多
关键词 incompressible pairwise incompressible surface twist crossing number pretzel knot puncture sphere rational knot
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A novel device for endoscopic submucosal dissection,the Fork knife 被引量:3
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作者 Hyun Gun Kim Joo Young Cho +7 位作者 Gene Hyun Bok Won Young Cho Wan Jung Kim Bong Min Ko Jin Oh Kim Joon Seong Lee Moon Sung Lee Chan Sup Shim 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第43期6726-6732,共7页
AIM: To introduce and evaluate the efficacy and technical aspects of endoscopic submucosal dissection (ESD) using a novel device, the Fork knife. METHODS: From March 2004 to April 2008, ESD was performed on 265 ga... AIM: To introduce and evaluate the efficacy and technical aspects of endoscopic submucosal dissection (ESD) using a novel device, the Fork knife. METHODS: From March 2004 to April 2008, ESD was performed on 265 gastric lesions using a Fork knife (Endo FS) (group A) and on 72 gastric lesions using a Flexknife (group B) at a single tertiary referral center. We retrospectively compared the endoscopic characteristics of the tumors, pathological findings, and sizes of the resected specimens. We also compared the en b/oc resection rate, complete resection rate, complications, and procedure time between the two groups. RESULTS: The mean size of the resected specimens was 4.27 ± 1.26 cm in group A and 4.29 ± 1.48 cm in group B. The en b/oc resection rate was 95.8% (254/265 lesions) in group A and 93.1% (67/72) in group B. Complete ESD without tumor cell invasion of the resected margin was obtained in 81.1% (215/265) of group A and in 73.6% (53/72) of group B. The perforation rate was 0.8% (2/265) in group A and 1.4% (1/72) in group B. The mean procedure time was 59.63 ± 56.12 min in group A and 76.65 ± 70.75 min in group B (P 〈 0.05). CONCLUSION: The Fork knife (Endo FS) is useful for clinical practice and has the advantage of reducing the procedure time. 展开更多
关键词 Fork knife Novel device Endoscopic submucosal dissection Flexknife PROCEDURE
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Comparative experiments of gas drainage in different types of drillings
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作者 LI Cheng-wu WEI Shan-yang +2 位作者 WANG Chuan GAO Tian-bao FU Yu-kai 《Journal of Coal Science & Engineering(China)》 2012年第2期129-133,共5页
Gas drainage effect is the utmost important factor for mining speed and mining safety. It has great meaning to study the effect of gas drainage. Comparative experiment of gas drainage in different types of drillings s... Gas drainage effect is the utmost important factor for mining speed and mining safety. It has great meaning to study the effect of gas drainage. Comparative experiment of gas drainage in different types of drillings shows that the initial rate of gas natural emission by hydraulic loosed cross drilling is 1.5 times more than that of parallel drilling, and the drilling gas at- tenuation coefficients reduces to 0.78 times, the effect of gas drainage is good. The ultimate quantity of gas drainage of parallel drilling, cross drilling, hydraulic loosed cross drilling are 859.1, 1 323.5 and 1 833.6 m3/100 m. The results of the measurement through these three kinds of drillings of 100 meters drilling is considered as following: cross drilling is 1.54 times more than that of parallel drillings, hydraulic loosed cross drilling are 2.13 times more than parallel drilling. The drainage rate of parallel drilling, cross drilling and hydraulic loosed cross drilling reached 10% to 15% in 3 months with the pre-draining time. Among these, the drainage effect of hydraulic loosed cross drilling increased by 46% than that of parallel drilling in three months. 展开更多
关键词 gas drainage cross drilling hydraulic looseness
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CLINICAL STUDY ON TREATMENT OF TRIGEMINAL NEURALGIA BY NEEDLING MENTAL AND MANDIBULAR FORAMINA
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作者 董宇翔 韩春霞 张二力 《World Journal of Acupuncture-Moxibustion》 2001年第1期33-35,共3页
In the present paper, 126 patients with neuralgia involving the mandibular branch of trigeminal nerve were treated mainly by puncturing the mental foramen and the mandibular foramen. The two foramina are both located ... In the present paper, 126 patients with neuralgia involving the mandibular branch of trigeminal nerve were treated mainly by puncturing the mental foramen and the mandibular foramen. The two foramina are both located in the focus through which the Stomach Channel of Foot Yangming passes. Among the 126 patients, 42 were attributed to the light type, 61 to the moderate type one and the other 23 to serious type. Acupuncture treatment was given once daily, 30 min every time, with 10 days being a therapeutic course. After 3 courses of treatment, results showed that 29 (69.1%) light type cases, 35(57.4%) moderate type cases and 6 (26.1%) serious type cases were cured. It displays that the less serious the symptom, the higher is the cure rate, and the shorter the duration of disease, the better is the therapeutic effect. 展开更多
关键词 Acupuncture therapy Mental and mandibular foramina Trigeminal neuralgia
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DF_7型机车启动电机传动轴修理中的问题及解决
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作者 宋锁奎 《铁道机车车辆工人》 2001年第9期16-16,共1页
DF7型机车启动电机传动轴,由于其转速高(3 000 rpm),传递扭矩大,因此其加工装配精度要求较高.在修理启动电机传动轴过程中遇到两个比较棘手的问题.一是轴承外圈与叉头轴承孔配合间隙的处理,二是十字销与轴承外圈轴向间隙的测量.根据多... DF7型机车启动电机传动轴,由于其转速高(3 000 rpm),传递扭矩大,因此其加工装配精度要求较高.在修理启动电机传动轴过程中遇到两个比较棘手的问题.一是轴承外圈与叉头轴承孔配合间隙的处理,二是十字销与轴承外圈轴向间隙的测量.根据多年的修理经验,摸索出解决这两个问题的方法,取得了良好的效果,现介绍如下. 展开更多
关键词 DF7型机车 内燃机车 启动电机传动轴 修理 轴承外圈 头轴承 配合间隙 十字销
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DESIGN AND ANALYSIS OF MULTI-MODE CLUSTER SAR
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作者 FanLuhong PiYiming HouYinming 《Journal of Electronics(China)》 2004年第5期401-406,共6页
Cluster Synthetic Aperture Radar (SAR) system is composed of a group of spaceborne SAR systems. With its agility of combination, this system can work in several different modes. In this letter, the basic configuration... Cluster Synthetic Aperture Radar (SAR) system is composed of a group of spaceborne SAR systems. With its agility of combination, this system can work in several different modes. In this letter, the basic configuration and the working mode of the system are presented.The special performance of the system compared with the conventional SAR system is indicated. 展开更多
关键词 Synthetic Aperture Radar (SAR) Cluster satellite Cross track interferometer SAR Along track interferometer SAR Wide swath
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Porous polymer supported palladium catalyst for cross coupling reactions with high activity and recyclability 被引量:1
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作者 SUN Qi ZHU LongFeng +2 位作者 SUN ZhenHua MENG XiangJu XIAO Feng-Shou 《Science China Chemistry》 SCIE EI CAS 2012年第10期2095-2103,共9页
Porous polymer supported palladium catalyst for cross coupling reactions with high activity has been successfully prepared by coordination of Pd 2+ species with Schiff bases functionalized porous polymer. The catalyst... Porous polymer supported palladium catalyst for cross coupling reactions with high activity has been successfully prepared by coordination of Pd 2+ species with Schiff bases functionalized porous polymer. The catalyst has been systemically investi-gated by a series of characterizations such as TEM, N 2 adsorption, NMR, IR, XPS, etc. TEM and N 2 isotherms show that the sample maintains the nanoporous structure after the modification and coordination. XPS results show that chemical state of palladium species in the catalyst is mainly +2. More importantly, the catalyst shows very high activities and excellent recycla-bility in a series of coupling reactions including Suzuki, Sonogashira, and Heck reactions. Hot filtration and poison of catalysts experiments have also been performed and the results indicate that soluble active species (mainly Pd(0) species) in-situ gener-ated from the catalyst under the reaction conditions are the active intermediates, which would redeposit to the supporter after the reactions. 展开更多
关键词 heterogenous catalysis PD coupling reactions nanoporous polymers
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