查询词典 selectivity

The results show that, firstly, Stellera chamaejasme L, which rely on their developed axial root system in the 10～40cm soil layer to occupy the competitive priority of volume, length, surface area and so on, in the case of their adaptive faculty to poor surroundings resulting from fruit picking, trampling and overgrazing as well as with the phenomenon of restrained growth among various plants, gradually become the dominant plant in the herbaceous community; secondly, this kind of degraded grassland has not displayed any general characteristic of degradation such as surface exposure, accumulative quantity of vegetation reduced, water loss, soil erosion and so on, therefor, it should be dealt with distinguishingly; thirdly, if"Stellera chamaejasme L Killer"and"Oxytropis ochrocephala Killer"invented by CAS are taken advantage of respectively in the bloom period of Stellera chamaejasme L and at the beginning of florescence of Oxytropis ochrocephala bunge by ultra-low volume spray of 1. 05L/hm〓 and 1. 35～165L/hm〓 dosage separately, the death rates of poisonous herbs may achieve above 95% and 92% correspondently; fourthly, this technology with the characteristics of high work efficiency, exclusive selectivity and convenient operation, is safe to non-target plants and other animals, and has no toxic or side-effect to environment; furthermore, an execution of"Stellera chamaejasme L Killer"spray and a two-year grazing prohibition can be effectively applied on degraded grasslands of"Weed and Poisonous plants Type".

结果表明：狼毒凭借发达的轴根系在10～40cm土层中形成的体积、长度、表面积等竞争优势，以及对采食、践踏、过度放牧所形成的不良环境的适应能力和异株克生现象的存在，逐步成为草群中的优势植物；毒杂草型退化草地没有表现出地表裸露、植物蓄积量减少、水土流失等一般性退化特征，对该类草地的治理应区别对待；应用中科院研制的'灭狼毒'和'灭棘豆'分别在狼毒盛花期和黄花棘豆初花期，以1.05L/hm〓、1.35～165L/hm〓的施用量超低容量喷雾，毒草的死亡率可达到95％、92％以上；该技术具有工效高、选择性专一、灭效高、操作简便，对非靶标植物和其它动物安全，对环境无毒副作用的特点；采用喷施'灭狼毒'+短期禁牧措施，可以有效治理毒杂草型退化草地。

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。

Impregnated by Pd, the Si/Al 0.33 sample with enhanced neighboring region has the highest n- dodecane hydroisomerization conversion and selectivity.

样品担载Pd后对正十二烷的加氢异构化反应表明，交界区扩大的Si/Al = 0.33的样品有最高的加氢异构化得率和选择性。

The reaction performance of Pt-Sn-Li/Al_2O3/FeCrAl catalyst was measured,and the properties of the catalyst were characterized.It was found that reaction temperature,LHSV and the molar ratio of hydrogen to alkane have greatly affected on the catalytic performance of the Pt-Sn-Li/Al_2O_3/FeCrAl catalyst.Under a set of optimal reaction conditions,at 0.1 MPa,470℃,the molar ratio of hydrogen to alkane of 4 and LHSV of 0.14 mL·m~(-2)·h~(-1),the dodecane conversion is 6%,and the dodecene selectivity is about 72%.

结果表明：工业催化剂的催化性能比至今实验室制备的γ-Al_2O_3和SBA-15颗粒负载型颗粒状催化剂的性能好；反应温度、液时空速和氢烃摩尔比对Pt-Sn-Li/Al_2O_3/FeCrAl金属基整体式催化剂脱氢性能都有重要影响，最适宜的反应条件是压力为0.1 MPa，反应温度为470℃，进料氢烃摩尔比为4和LHSV为0.14 mL·m~(-2)·h~(-1)，此时十二烷的转化率约为6%，十二烯的选择性约为72%；活性组分涂层与金属基体结合良好。

The influences of the composition of the catalysts, reaction temperature, space velocity and mol ratio of benzene and dodecylene on the conversion of dodecylene and the selectivity were researched.

在微型液相固定床反应器上考察了反应漫度，空速，磷钨酸负载量以及苯烯摩尔比等反应条件对催化剂性能的影响。

The electrodes have high selectivity, which can separate the electroanalytical signals of the solution components.

这种电极具有高选择性，能够将溶液中成分的电分析信号进行分离。

Recently, study on the ISEs with anti-Hofmeister selectivity pattern is an important and interesting subject in the field of electrochemistry and electroanalytical chemistry.

新型传感器材料特别是新型选择性载体的设计、合成和应用不仅是离子选择性电极研究的一个重要方向，而且也是现代化学关注的主要问题。

Recently, study on ion-selective electrodes with anti-Hofmeister selectivity pattern is an important and interesting project in the fields of electrochemistry and electroanalytical chemistry.

近年来，金属配合物作为载体呈现的反Hofmeister行为的阴离子选择性电极是电化学和电分析领域中公认的活跃研究课题。

Recently, study on ion-selective electrodes with anti-Hofmeister selectivity pattern is an important and interesting project in the fields of electrochemistry and electroanalytical chemistry.

研究发现，以呋喃甲醛甘氨酸合铜为载体的电极对水杨酸根离子有高的选择性并呈现出反Hofmeister选择序列行为。

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。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。