环
- 与 环 相关的网络例句 [注:此内容来源于网络,仅供参考]
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Macrocycle with two pyridyl unitsZ-protected groups in the di-ester formed from esterification of Z-Glycine with 2,6-bishydroxymethyl pyridine was removed and thenconverted into Ts-protected group.
本论文以天然氨基酸为手性源,以芳杂环为大环分子的刚性因素,研究它们的环合反应和分子结构,为此设计了下列三种结构类型的大环分子:一。
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The structure characters of this kind of molecules were discussed. The results show that the phenyl group located in the 4- or 5- position of pyrryl ring are not coplanar with the pyrryl ring.
对这类吡咯环上4或5-位有芳环取代基时化合物的晶体结构特征进行了扼要讨论,晶体衍射实验结果表明,4, 5-位上的芳环与吡咯环本身处于非共平面结构。
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The invention discloses an elastic sectionalization ring address binding method in the network transmission technological domain, which is characterized by the following: realizing the binding of RRP ring node MAC address and IP address through ATD frame in the extended RPR protocol; without adding extra system resource consumption; converging rapidly for topology after the RPR looped network occurs switching; providing address binding information for over three layered report to transfer and utilize.
本发明涉及传输网络技术,公开了一种弹性分组环地址绑定方法,使得在不增加额外系统资源消耗的情况下实现RRP环节点MAC地址和IP地址的绑定,并且在RPR环网发生倒换后,拓扑可快速收敛。本发明中,通过扩展RPR协议中的ATD帧,在广播ATD帧的同时携带MAC地址和IP地址绑定的信息,实现所有RPR环节点的MAC地址和IP地址的绑定,该地址绑定信息可供三层以上报文转发使用。
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In addition, the complemented semiring is defined and it is proved that the complemented semiring is also non-zeroic semiring and so there exist be non—zero ζ_s-injective modules.
另外,本文定义了一类新半环——可补半环,并证明出可补半环S必是non-zeroic半环,因而存在非零?
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New reactions found in this program include: photoinduced regioselective free radical addition to aromatic imines;photoinduced Dielse-Alder reactions of aromatic imines for synthesis of tetrahydroquinoline derivatives;Photoinduced radical cation mediated selective ring opening reaction of epoxides;Formation of novel macrocyclic crown ethers by photoinduced reaction of diazonaphthaquinones;photoinduced selective desilylation of silyl ethers.
用这种方法成功的发现了下列在有机合成中有意义的新反应:(1)光诱导产生的自由基正离子诱导的自由基对芳香亚胺的区域选择性加成反应;(2)用光诱导的芳香亚胺的Diels-Alder反应合成四氢喹啉衍生物;(3)经光诱导产生的自由基正离子基诱导的环氧化物选择性开环反应;(4)重氮萘酮在环醚中经光诱导反应形成新奇的大环冠醚;(5)硅醚的光诱导选择性脱硅基反应。
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The present invention concerns the compounds having the formula N-oxides, salts, stereoisomeric forms, racemic mixtures, prodrugs, esters and metabolites thereof, wherein R1 and R8 each are H, optionally substituted C1-6alkyl, C2-6alkenyl, C3-7cycloalkyl, aryl, Het1, Het2; R1 may also be a radical of formula (R11aR11b)NC(R10aR10b)CR9-; t is 0, 1 or 2; R2 is H or C1-6alkyl; L is -C-,-O-C-,-NR8-C-,-O-C1-6alkanediyl-C-,-NR8-C1-6alkanediyl-C-,-S2-,-O-S2-,-NR8-S2 ; R3 is C1-6alkyl, aryl, C3-7cycloalkyl, C3-7cycloalkylC1-4alkyl, or arylC1-4alkyl; R4 is H, C1-4alkylOC, carboxyl, aminoC, mono- or di(C1-4alkyl)aminoC, C3-7cycloalkyl, C2-6alkenyl, C2-6alkynyl or optionally substituted C1-6alkyl; R5 and R6 are H or C1-6alkyl.
本发明涉及右式化合物其N-氧化物、盐、立体异构形式、外消旋混合物、前药、酯及代谢物,其中R 1 及R 8 各是氢、C 1-6 烷基、C 2-6 烯基、C 3-7 环烷基、芳基、Het 1 、Het 2 ;R 1 也可以是式(R 11a R 11b )NC(R 10A R 10b )CR 9 -之基;t是0、1或2;R 2 是氢或C 1-6 烷基;L是-C-、-O-C-、-NR 8 -C-、-O-C 1-6 烷二基-C-、-NR 8 -C 1-6 烷二基-C-、-S 2 -,-O-S 2 -、-NR 8 -S 2 -;R 3 是C 1-6 烷基、芳基、C 3-7 环烷基、C 3-7 环烷基C 1-4 烷基或芳基C 1-4 烷基;R 4 是氢、C 1-4 烷基OC、羧基、氨基C、一-或二(C 1-4 烷基)氨基C、C 3-7 环烷基、C 2-6 烯基、C 2-6 炔基或任选被取代的C 1-6 烷基;R 5 及R 6 是氢或C 1-6 烷基。
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This dissertation successfully fabricated cross-linked polysiloxanes under base catalysts such as potassium hydroxide siloxanolate or tetramethylammonium hydroxide (Me_4NOH) siloxanolate by anionic ring-opening copolymerization of cyclosiloxanes and Polyhedral Oligomeric Silsesquioxanes as multifunctional monomers.
本论文首次通过阴离子开环共聚,成功地将POSS大分子作为多官能团单体,与环硅氧烷在KOH硅醇盐或Me_4NOH硅醇盐等碱性催化剂的作用下,直接合成交联聚硅氧烷:通过调节POSS大分子和环硅氧烷单体的种类以及化学计量比,可合成出一系列不同种类和不同交联密度的交联聚硅氧烷;并对其阴离子开环共聚机理以及极性调节剂DMAc对凝胶时间的影响进行了详细讨论;同时借以凝胶含量和溶胀比、GPC、FT-IR、固体~(13)C和~(29)Si NMR、WAXD、DSC以及TG等手段对所得聚合物的微观结构以及热性能进行了详细考察。
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According to the definition and the distribution of VSR's voltage space vector, the introduction of a rule-based SVPWM current control strategy, with non-fixed switching frequency and dual hysteresis loops, that obviously improves the performance of current control. Based on two kinds of control strategies of VSR under unbalanced grid condition, the introduction of a new VSR control strategy featuring undamped-oscillation that simplifies the controller structure and effectively improves VSR's performance under unbalanced grid condition. A systematic description of the state switching in trilogic PWM signal generation of threephase CSR by using the conversion between bilogic and trilogic switching functions.
作者在如下工作的基础上对PWM整流器的一些关键问题提出了自己的研究思路、观点和方法:根据PWM整流器网侧矢量关系,直观地描述了其四象限运行的基本原理及特征;定量分析了VSR、CSR的PWM换相过程及波形特征;引入等效变压器模型并详细分析了VSR、CSR基于d—q模型的动、静态特性;提出了满足四象限有功、无功运行指标时的VSR交流侧电感设计方法;并提出了依据控制系统跟随性和抗扰性性能指标设计VSR、CSR直流侧储能元件的参数计算方法;在研究了VSR电流控制策略基础上,提出了影响VSR电流控制的几个要素,并进行了定量分析;根据VSR空间电压矢量的定义及分布,提出了基于规则控制的不定频滞环空间矢量PWM电流控制策略,并由此提出了具有双滞环特性的不定频滞环优化SVPWM电流控制策略,有效地改进了滞环PWM电流控制性能。
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In this dissertation, two series of rare earth initiators: rare earth tri (2, 6-di-tert-butyl4-methylphenolate) and rare earth calixarene complex have been developed to ring-opening polymerize 2, 2-dimethyltrimethylene carbonate, trimethylene carbonate and ε-caprolactone at mild conditions. Both the polymerization features and mechanisms are discussed in details.
本论文为环碳酸酯、内酯的开环聚合开发了两类新型低毒性稀土催化剂:三(2,6-二叔丁基-4-甲基苯氧基)稀土配合物和对叔丁基杯芳烃稀土配合物,都可以在温和的反应条件下单组分引发2,2-二甲基三亚甲基环碳酸酯、三亚甲基环碳酸酯和ε-己内酯聚合,合成各种分子量的均聚和共聚材料,考察了催化剂结构、聚合条件等对聚合的影响,深入研究了聚合机理。
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METHODS: Collaborative meta-analyses were undertaken of 194 unconfounded randomised trials of adjuvant chemotherapy or hormonal therapy that began by 1995. Many trials involved CMF (cyclophosphamide, methotrexate, fluorouracil), anthracycline-based combinations such as FAC (fluorouracil, doxorubicin, cyclophosphamide) or FEC (fluorouracil, epirubicin, cyclophosphamide), tamoxifen, or ovarian suppression: none involved taxanes, trastuzumab, raloxifene, or modern aromatase inhibitors.
对194个开始于1995年的关于辅助化疗或激素治疗的随机试验进行meta分析,许多试验包含了CMF(环磷酰胺、氨甲喋呤、氟尿嘧啶),蒽环药物为基础的联合化疗比如FAC(氟尿嘧啶、阿霉素、环磷酰胺)或FEC(氟尿嘧啶、表阿霉素、环磷酰胺)及他莫昔芬或卵巢去势;无一包含紫杉烷类、赫赛汀、雷洛昔芬及芳香化酶抑制剂。
- 推荐网络例句
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Do you know, i need you to come back
你知道吗,我需要你回来
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Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.
1〕 杨银书,王祥生,李德昌。安徽省首次发现嗜群血蜱。
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Chapter Three: Type classification of DE structure in Sino-Tibetan languages.
第三章汉藏语&的&字结构的类型划分。