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21.
1H and 13C NMR spectra of cis- and trans-3-(2-[2-(4-methylphenyl)ethenyl]phenyl])sydnones, the first stilbene-substituted mezoionic oxadiazolium rings, were fully assigned combining the information in various solvents, such as deuterated benzene, acetone and chloroform, using 2D NMR techniques.  相似文献   
22.
A rigorous side by side comparison of miniature planar potassium-selective electrodes with hydrogel and potassium hexacyanoferrate(II)/(III) doped polypyrrole (PPy/FeCN) based inner contacts is presented. The planar electrodes were manufactured by screen printing as four- and five-site arrays on ceramic substrates. These electrode arrays were incorporated into a flow-through cell, which could accommodate nine electrode sites. Two identical flow cells were connected in series and the effect of the inner contacts on the analytical performance of the respective electrodes has been critically evaluated. The time necessary to reach steady state conditions has been determined and the effect of experimental parameters (temperature, ambient light intensity, CO2, and O2 concentration of the sample) on the potential stability of the electrodes was analyzed. At controlled temperature, the drift of the planar potassium electrodes with hydrogel and PPy/FeCN solid contact were 0.11±0.02 mV h−1 and 0.03±0.007 mV h−1, respectively. The experimental data proved that there is no aqueous film formation between the PPy/FeCN film and the potassium-selective solvent polymeric membrane.  相似文献   
23.
Chemical compounds containing platinum have been employed since 1978 as drugs to beat certain type of tumours. Nevertheless, besides of their exceptional antitumoral properties, these drugs also have important deleterious side effects, such as, nephrotoxicity and ototoxicity.A study of Pt accumulation and a speciation analysis has been performed by ICP-MS in samples from kidney and inner ear in a controlled population of Wistar rats treated with, either, cisplatin, carboplatin or oxaliplatin. The results on Pt accumulation point out to drug structure and not only to Pt content as the responsible for the alteration of organ functionality.Speciation studies in the samples from kidney and inner ear were performed coupling two-dimensional liquid chromatography (2D-LC) to ICP-MS. Size exclusion (SEC) and anion exchange fast protein liquid chromatography (FPLC) was employed for 2D orthogonal separation. After these separations, free drug peaks were not observed in any of the samples.The binding of Pt to biomolecules was demonstrated by SEC and, independently of the drug used, Pt eluted as two main bands with molecular weights of 12 kDa and 25-65 kDa for inner ear samples, and as two different bands with 20 kDa and 50-60 kDa in the samples from kidney. However, the relative band intensity presented important differences for the three drugs. Using the same chromatographic conditions, it was shown that a metallothionein (MT) standard eluted in the same position as some of the cytosolic Pt-biomolecules.High Pt-containing fractions eluting from the SEC column were analysed by anion exchange FPLC after a preconcentration step. Among the different preconcentration methods tested, sample focusing on the head of the FPLC column shows main advantages. In this way, the separation by 2D chromatography of the high molecular Pt-species has been considerably improved.  相似文献   
24.
A highly-efficient preparative procedure for ( R, S )- and ( S, S)-pyrroHdine-2-carboxyHc acid 3,5-dioxa-4-boracyclohepta[2, 1-α ; 3,4-α′] dlnaphthalen-4-yl esters [ namely ( R, S )-BNBAP and (S, S )-BNBAP] is described and the crystal structure of (R, S )-BNBAP was obtained. The data indicate that ( R, S )-BNBAP is a spirocyclic inner borate salt with almost normal te-trahedral configuration. This structural form may be the basic reason for their high chemical, optical and thermodynamic sta-bility.  相似文献   
25.
《Microelectronics Reliability》2014,54(9-10):1953-1958
The effects of silicon etching using the Bosch process and LPCVD oxide deposition on the performance of open TSVs are analyzed through simulation. Using an in-house process simulator, a structure is generated which contains scalloped sidewalls as a result of the Bosch etch process. During the LPCVD deposition step, oxide is expected to be thinner at the trench bottom when compared to the top; however, additional localized thinning is observed around each scallop. The scalloped structure is compared to a structure where the etching step is not performed, but rather a flat trench profile is assumed. Both structures are imported into a finite element tool in order to analyze the effects of processing on device performance. The scalloped structure is shown to have an increased resistance and capacitance when compared to the flat TSV. Additionally, the scalloped TSV does not perform as well at high frequencies, where the signal loss is shown to increase. However, the scallops allow the TSV to respond better to an applied stress. This is due to the scallops’ enhanced range of motion and displacement, meaning they can compensate for the stress along the entire sidewall and not only on the TSV top, as in the flat structure.  相似文献   
26.
《Analytical letters》2012,45(4):529-542
Abstract

A simple and reproducible method for increasing the sensitivity of fluorescence measurements by a factor of 2.0–2.5 is presented. Data are presented to explain: the deviation from the expected theoretical increase in sensitivity of 4.0; wavelength dependency and subsequent problems arising from enhanced inner filtering effects.  相似文献   
27.
In order to construct a class of new Turaev-braided group category with nontrivial associativity, the concept of a quasitriangular quasi-Turaev group coalgebras was recently introduced. Inside the definition, the conditions of invertibility of the R-matrix R and bijectivity of the antipode S are required. In this article, we prove that the antipode of a quasitriangular quasi-Turaev group coalgebra without the assumptions about invertibility of the antipode and R-matrix is inner, and a fortiori, bijective. As an application, we prove that for a quasitriangular quasi-Turaev group coalgebra, two conditions mentioned above are unnecessary.  相似文献   
28.
In the present paper, self-adjoint operator and completely continuous operator on soft inner product spaces have been introduced and some basic properties of such operators are studied.  相似文献   
29.
Through‐silicon via (TSV) technology provides much of the benefits seen in advanced packaging, such as threedimensional integrated circuits and 3D packaging, with shorter interconnection paths for homo‐ and heterogeneous device integration. In TSV, a destructive cross‐sectional analysis of an image from a scanning electron microscope is the most frequently used method for quality control purposes. We propose a quantitative evaluation method for TSV etch profiles whereby we consider sidewall angle, curvature profile, undercut, and scallop. A weighted sum of the four evaluated parameters, nominally total score (TS), is suggested for the numerical evaluation of an individual TSV profile. Uniformity, defined by the ratio of the standard deviation and average of the parameters that comprise TS, is suggested for the evaluation of wafer‐to‐wafer variation in volume manufacturing.  相似文献   
30.
姚蔷  叶佐昌  喻文健 《半导体学报》2015,36(8):085006-7
针对三维芯片中硅通孔(through-silicon via, TSV)的准确电学建模问题,本文提出了一种电阻电容(RC)电路模型以及相应的有效参数提取技术。该电路模型同时考虑了半导体效应与静电场影响,适合于低频与中频的电路信号范围。该方法采用一种基于悬浮随机行走(floating random walk, FRW)算法的静电场电容提取技术,然后将它与刻画半导体效应的MOS电容结合,形成等效电路模型。与Synopsys公司软件Sdevice所采用的对静电场/半导体效应进行完整仿真的方法相比,本文方法计算效率更高,并且也能处理一般的TSV电路版图。对多个含TSV的结构进行了计算实验,结果验证了本文方法在从10KHz到1GHz频率范围内的建模准确性,也显示出它相比Sdevice方法最多有47倍的加速比。  相似文献   
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