选择性的
- 与 选择性的 相关的网络例句 [注:此内容来源于网络,仅供参考]
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The organoboron compounds in this paper are based on triarylboranes, boronic acids and boronic esters. The structure-property relationship and sensing mechanism are elucidated. Organoboron compounds as Lewis acid can be used as fluoride probe with high sensitivity and selectivity because they have a unique LUMO in which the π-conjugation is divergently extended through the vacant p-orbital of the boron atom. The complexation of the boron π-electron systems with fluoride ion would interrupt the π-conjugation extended through the boron atom, causing the change of photophysical properties.
介绍了基于三芳基硼化合物、硼酸和硼酸酯的有机硼化合物在氟离子检测中的应用,评述了这些化合物的结构和检测性能之间的关系,讨论了检测机理,即有机硼化合物中硼原子空的p轨道使其作为路易斯酸能够选择性地结合氟离子,硼原子与氟离子的结合破坏了硼中心与芳香取代基的p-π共轭,引起有机硼化合物光物理性质的变化,从而实现对氟离子的高选择性检测。
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By time-varying filtering, we realize the signal selectivity and interference suppression, especially for the signals with time-varying power spectrum. It is shown herein that conventional eigenstructure based methods are lower dimensional special case of the time-frequency subspace fitting method. The closed-form array response estimation algorithms for blind source separation in wireless communication is also developed in the dissertation by exploiting the data structure of second-order statistics of the array output in the presence of multipath. The proposed method achieves array response estimation with little constraint on signal property and propagation environment such as scatters or angular spread. Moreover, the array utilized here can be of arbitrary geometry and even uncalibrated. Since the closed-form solution is obtained, no misconvergency may occur and large amount of computation can be saved. The equivalent feed model and corresponding optimization designation are proposed to realize the downlink multi-user selective transmission. By coherent and non-coherent superposition of the electromagnetical field, multiple beams can be formed using a single array, so that each co-channel user signal is transmitted in each beam and will not interfered with each other. The proposed system scheme implements the digital beamforming and the channel allocation in the base band, therefore is suitable for the utilization of the radio software technology. The feasibility and effectiveness of the proposed model are proved by the RF experiment.
在窄带条件下,GSC-SSF方法还可以提高阵列的虚拟孔径,从而提高估计的性能;可以证明,Cyclic DOA 和SC-SSF方法可看作该方法的特例或近似; 3、提出了二维GSC-SSF方法和宽带谱相关DOA矩阵方法,利用信号的循环平稳特性解决了宽带条件下二维 DOA 估计问题,并具有阵元数少、计算量较小的特点; 4、提出了时频子空间拟合和宽带时频DOA估计算法,将联合时频分析的理论和方法引入到阵列信号的空间谱估计研究中,利用时变滤波实现信号选择性测向和干扰抑制,特别适合于谱时变信号;可以证明传统特征结构法可看作是时频子空间拟合方法的特例; 5、提出了多用户环境下阵列响应的估计方法——CARE方法,该方法对信号结构和传播参数(主要是散射源分布与角度散布)的约束较少,适用于各种几何结构的阵列甚至未校准的阵列,能够直接得到阵列响应的闭式解,因此计算量小、稳健性好,不存在收敛问题; 6、提出了针对多用户下行选择性发送的阵列等效激励模型、优化设计方法及其系统实现方案,通过空间场的相干叠加与非相干叠加使得单一阵列能够形成多个波束,并保证各波束内的用户信号各不相同且相互干扰最小;其系统方案具有在基带实现数字波束成形、信道分配并便于软件无线电实现的特点,其有效性已得到外场实测数据的证实。
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The dissertation mainly consists of two parts:1. The Reaction Chemistry of Alkynes under Palladium Catalysis Part 1 studies the reaction α,β-unsaturated carbonyl compounds with alkenylpalladium intermediate generated by nucleopalladation, and discovered 1 the Pd-catalyzed tandem addition reaction of halides, alkynes and α,β-unsaturated carbonyls,2 the four-component tandem addition reaction of halides, alkynes and α,β-unsaturated carbonyls, 3 the tandem intramolecular oxypalladation-conjugate additionreaction of alkynoic acids with α,β-enals. These new reactions provide notonly efficient highly stereoselective methods for the synthesis of γ,δ-unsaturated,polyunsaturated carbonyl compounds and γ-lactonic aldehydes, but also thebasic transformations for a number of C-C bond formation reactions which can be usedto design synthesis of many acyclic, cyclic or polycyclic compounds.
本论文的主要工作分为两个部分:一、钯催化下炔烃的反应化学在本小组前人工作的基础上,我们详细研究了炔烃亲核钯化产生的烯基钯中间体与α,β-不饱和羰基化合物的反应,发现两价钯催化下卤离子-炔烃-α,β-不饱和醛酮的串联加成反应、卤离子-炔烃-α,β-不饱和醛酮的西组分串联加成及炔酸分子内氧钯化-串联Michael型加成反应;由此发展了γ,δ-不饱和醛酮、多不饱和羰基化合物和带有醛酮基侧链的γ-丁内酯衍生物的高立体选择性合成方法,这一过量卤离子存在下的烯基钯对α,β-不饱和羰基化合物共轭加成反应的发现,为大量碳-碳键形成反应的实现提供了基础,使我们能够从这一基本反应出发,设计和开发多种分子内、分子间的碳碳成键反应,以好的立体、区域选择性组建开链、环状及多环类型的化合物。
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A polar sensitive probe with selective marks prepared by the invention can be used for compounds comprising mercapto. Owning to the introduction of the maleimide group, the probe can be used for the measurement and research of marks of biomacromolecules that comprise the mercapto and adjacent regional polarity change situations of the mercapto, in particular to the research of the selective marks of the mercapto and the adjacent regional polarity change situations of the mercapto in protein.
本发明制备出一种能够用于含有巯基的化合物的选择性标记的极性敏感探针,该探针由于马来酰亚胺基团的引入,可以用于含有巯基的生物大分子的标记及巯基附近区域极性变化情况的测定和研究,特别是蛋白质中巯基的选择性标记和巯基附近极性变化情况的研究。
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The experimental data demonstrated that there was a nasalward directional preference in oath OKN system under both close loop and open loop conditions, and the nasalward OKN gain evoked by stimulation of nasal retina was much higher than that at temporal retina. ms indicates that OKN nasalward preference is mairily derived from the nasal retina, i. e. the direct path1Vay of OKN dominates the indirect pathway in cat's OKN system. The gains of temporalward and nasalward OKN from temporal retina are much less than those of nasalward OKN from nasal retina. It is suggested that the indirect pathway of OKN in the cat only possesses a supplementary function, Which probably plays an important role in temporalward OKN eye-movments in relation to binocular vision.
实验结果显示:高速度刺激的闭环OKN反应及开环OKN反应均对鼻向运动刺激有明显的方向选择性;半侧视网膜刺激时,鼻侧半视网膜的鼻向OKN增益明显高于颞侧半视网膜的鼻向增益,说明猫的OKN眼动反应以跟踪鼻向运动为主,并且这种对鼻向运动刺激的选择性主要来源于鼻侧半视网膜,亦即来源于OKN直接通路;颞侧半视网膜的鼻、颞向眼动增益均明显低于鼻侧半视网膜的鼻向眼动增益,说明猫的OKN系统的间接通路在OKN眼动控制中起辅助作用,并可能主要对颞向OKN眼动起作用从而与双眼视觉功能相关。
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It was found that La〓 does not affect the binding affinity between calmodulin and Polistes Mastoparan, a known calmodulin binding peptide, neither the conformation of the ternary complex. Excessive amount of La〓 result in the decrease of the binding constant and the disrupted conformation. The binding affinity of La〓 to calmodulin increased in the ternary complex (La〓-CaM-Mas/Mas X), which suggested the coordination between the two global domains. The binding priority between the two global domains is also changed: La〓 more is likely to bind to the C-terminal of calmodulin than to N-terminal, thus facilitates the binding of Mas/Mas X to the C-terminal of calmodulin as the first step of the Mas/Mas X binding.
在以钙调蛋白结合肽—Polistes Mastoparan和Mastoparan X为对象的研究中,我们发现,除非过量,否则La〓的存在不影响钙调蛋白与Mas间的结合常数以及构象;过量的La〓(La〓/CaM摩尔比>4)将引起钙调蛋白结合功能的下降,同时明显改变金属-钙调蛋白-Mas三元复合物的构象;La〓对Ca〓CaM-Mas的N末端表现高度选择性,显示了在三元复合物中两种离子间的协同效应;在三元体系中,La〓与钙调蛋白的亲和力明显上升,而且亲和力上升的程度因钙调蛋白结合肽的不同而有明显差异,显示了作用的选择性;Mas和MasX的存在改变了La〓在钙调蛋白上的结合顺序,La〓很可能优先与C末端结合,从而使Mas/Mas X首先与C末端结合,该顺序与钙离子相同;La〓的参与使三元复合物在动力学上更加稳定。
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In the area of selective catalysis, they will soon publish the first examples of stereochemically thoroughly investigated Enantioselective Organo-Autocatalysis, a process that demonstrates conceptually new catalysis design strategy and also provides structurally well-defined small-molecule models that may help explain the origin and maintenance of homochirality fundamental to the functions of biological systems.
在相邻的选择性催化领域,他们即将发表设计发现的首例有机小分子催化的高立体选择性自复制过程(Enantioselective Organo-Autocatalysis),此类反应不仅避免了繁琐的催化剂和产物分离问题,更有意义的是充分利用了产物自身的催化功能,并为分子手性单一性这一生命体根本特征的起源和自发维持提供了第一个简洁的小分子模型系统。
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They are①ANN based nonlinear coding method to reduce coding delay②the conversion method of CBR streams to VBR streams to make the packeting delay negligible③human perception based main and subordinate packet method to reduce the influence of packeting delay④cell selective discarding and datagram selective shorten method to reduce queuing delay by alleviating the load of links⑤multitask cell or datagram multiplexing method to reduce packeting delay.
作者研究的重点,在于提出了若干降低编码、信息分组装配和分组排队时延的新方法,它们是:降低编码时延的ANN非线性编码法、大幅度降低分组装配时延的CBR码流VBR转换法、基于人耳听觉特性的主次信息分组装配降低时延法、新的降低排队时延和网络拥塞状态的信元选择性删除和数据报选择性截短适配法,以及降低分组装配时延的多任务复合装配法。
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In others with double-armed receptors, the probes 4-(N,N-bisacetoxyethylaminomethyl)-7-methoxycoumarin.(B3) and 4-N,N- bis(diethylaminodithiocarboxyethyl aminomethyl-7-methoxycoumarin (B4) with pronounced fluorescence enhancement response to special heavy and transition metal ions were proposed as PET mechanism; for those with double-armed receptors following ICT mechanism, their performances are influenced by not only the structure of the receptors but also the attaching position of it.
双臂香豆素类荧光分子探针体系中,我们研究了含有不同杂原子的识别基团对PET型荧光探针识别性能的影响,优化了探针的选择性,得到了可以选择性识别某种过渡金属和重金属离子的荧光增强型分子探针4--7-甲氧基香豆素(B3)和4--7-甲氧基香豆素B4而在ICT型荧光探针的研究中,我们发现具有不同杂原子的识别基团可以对识别性能产生影响的同时,连接位置的改变也对识别能力有很大的影响。
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In order to disclosure the reason why the electrocatalysis activeness and selectivity droped after being used several hundred hours continuously, the x-ray diffraction, scanning electron microscopy and energy dispersive spectroscope have been used to characterize the surface condition variations of Monel metal. The results indicated: Monel metal belongs to the Cu-Ni alloy around the electrolysis experiment.And after being used for 600hr, the surface layer element composition and geometry distribution of the alloy changed, namely in the alloy the Cu element /which superficial free enthalpy was smaller,"concentrated" to the alloy surface,and formed one kind of marble structure microcrystallite.Thus the electrode surface becamed rough a
为了揭示蒙乃尔合金阴极在连续使用数百个小时后电催化活性剂选择性下降的原因,采用X射线衍射仪、电子扫描电镜和电子能谱分析仪对电解实验所用的蒙乃尔阴极材料在电解实验前后的表面状态进行了表征,结果表明:所使用的蒙乃尔合金阴极材料在电解实验前后均属于Cu-Ni合金,使用600hr后,由于表面层元素组成和几何排布发生了变化,即合金中表面自由焓较小的Cu元素向合金表面&富集&,形成一种大理石结构的微晶,表面粗糙、不均一,这是造成其对硝基苯电还原的催化活性及选择性随着使用时间延长而逐渐下降的主要原因,同时也为此类电极的修饰改进提供了方向。
- 推荐网络例句
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However, as the name(read-only memory)implies, CD disks cannot be written onorchanged in any way.
然而,正如其名字所指出的那样,CD盘不能写,也不能用任何方式改变其内容。
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Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.
镀锌钢托盘多用于出口,替代木托盘,免薰蒸,符合欧盟、北美各国对出口货物包装材料的法令要求;喷涂钢托盘适用于重载上货架之用,托盘表面根据需要制作成平板状、波纹状及间隔形式,满足不同的使用要求。
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A single payment file can be uploaded from an ERP system to effect all pan-China RMB payments and overseas payments in all currencies.
付款指令文件可从您的 ERP 系统上传到我们的电子银行系统来只是国内及对海外各种币种付款。