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11.
This determination of salicylate in blood serum is based on application of an immobilized enzyme electrode. Salicylate hydroxylase (E.C.1.14.13.1) is chemically immobilized onto a pig intestine mounted on an oxygen electrode. The signals are monitored amperometrically and the resulting output voltage is read using a simple adapter. The experimental parameters and possible interferences are discussed. Samples containing 1.0 × 10?5?1.87 × 10?3 M (1.6–300 μg ml?1) salicylate were assayed with relative standard deviations between 1.3% and 6% and recoveries between 98.7 and 103%. Results obtained by the proposed method and by the established clinical method for randomly spiked pooled serum samples correlated well (r = 0.99). 相似文献
12.
S. A. Nabi E. S. M. Abu-Nameh N. Rahman M. I. H. Helaleh 《Analytical and bioanalytical chemistry》1998,360(1):140-141
A simple, fast and sensitive titrimetric method has been developed for the determination of tetracycline hydrochloride in human urine using m-dinitrobenzene as color agent and Dowex 1 × 8 as detection medium. 相似文献
13.
Syed Ashfaq Nabi Rifaqat AliKhan Rao Ahsan Rasheed Siddiqui 《Fresenius' Journal of Analytical Chemistry》1982,311(5):503-506
Summary Stannic selenoarsenate samples have been prepared by adding a mixture which is 0.05 M in sodium arsenate and 0.05 M in sodium selenite to a 0.05 M solution of stannic chloride in different volume ratios at pH 1. Its ion-exchange properties, pH titration curves and X-ray pattern were studied. Adsorption behaviour of 24 metal ions in different solvent systems has been examined. The analytical importance of this material has been demonstrated by achieving the following binary and ternary separations: Hg2+-Cd2+, Co2+-Fe3+, Cu2+-Fe3+, Hg2+-Zn2+-Al3+, Hg2+-Cu2+-Al3+, Hg2+-Ni2+-Al3+, Hg2+-Zn2+-Fe3+ and Hg2+-Ni2+-Fe3+. A comparison of the ion-exchange properties of this material has also been made with some other tin(IV) based ion-exchangers.
Synthese, Ionenaustauscher-Eigenschaften und analytische Anwendungen von Zinn-Selenoarsenat: Vergleich mit anderen Heteropolysalzen
Zusammenfassung Zinn-Selenoarsenat wurde durch Mischen von 0,05 M Natriumarsenat-, 0,05 M Natriumselenitund 0,05 M Zinn(IV)-Chlorid-Lösungen bei pH 1 in verschiedenen Verhältnissen hergestellt. Die Ionenaustauscher-Eigenschaften, pH-Titrationskurven sowie Röntgendiagramme wurden untersucht und das Adsorptionsverhalten von 24 Metallionen in verschiedenen Lösungsmittelsystemen geprüft. Die analytische Verwertbarkeit wurde an Hand der folgenden Trennungsmöglichkeiten gezeigt: Hg2+-Cd2+, Co2+-Fe3+, Cu2+-Fe3+, Hg2+-Zn2+-Al3+, Hg2+-Cu2+-Al3+, Hg2+-Ni2+-Al3+, Hg2+-Zn2+-Fe3+, Hg2+-Ni2+-Fe3+. Vergleiche mit anderen Ionenaustauschern auf Zinn(IV)-Basis werden ebenfalls beschrieben.相似文献
14.
Summary The thin-layer chromatographic behaviour of 28 phenolic compounds was studied on semicrystalline stannic tungstate layers using various solvent systems of which formic acid and n-butanol-formic acid were found to be the most useful for the separation of these compounds. Dimethyl sulphoxide was found to act as a self detector for a number of phenols. An interesting feature of the study of phenols using stannic tungstate is the novel separation of different isomeric compounds. A number of binary, ternary and quarternary separations of bioanalytical and immunophysiological importance have been achieved. 相似文献
15.
Mohsin Qureshi S. Ashfaq Nabi Ali Mohammad Pushkin M. Qureshi 《Molecular Crystals and Liquid Crystals》2013,570(1-4):13-18
Abstract A new relation between the melting points of organic solids and their reactivity has been established. The relation follows √? = - k log Mp + C where ? is the thickness of the colored boundary Mp is the melting point of the organic solid and k and C are constants. 相似文献
16.
Meisam Amiri Vahid Esfahanian Mohammad Reza Hairi-Yazdi Mohsen Esfahanian Amir Mohammad Fazeli Ali Nabi 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(2):191-207
With the stricter limitations on both fuel consumption and air pollution, the advantages of a hybrid electric vehicle are becoming more evident than ever. In the present study, an energy management system for a hybrid electric vehicle is developed. Because the plant under consideration is nonlinear, multi-domain, time-varying, has multiple uncertainties and, in addition, the designed control strategy must be able to obey the driver's commands and achieve the par-internship for a new generation of vehicle regulations, the fuzzy logic approach is chosen. A feed-forward hybrid vehicle simulation model is used to demonstrate the validity and the convenience of the current approach and its results have been compared with the other parallel hybrid electric vehicle control strategies. Simulation results show considerable improvement in the efficiency of the internal combustion engine and, consequently, fuel consumption and acceleration performances. 相似文献
17.
Photodegradation and flow-injection determination of simetryn herbicide by luminol chemiluminescence detection 总被引:1,自引:0,他引:1
A novel and simple flow injection chemiluminescence method is reported for the determination of simetryn, a common herbicide. The method is based on the direct oxidation of luminol by the photoproducts of the simetryn in alkaline medium in the absence of catalyst/oxidant. The linear concentration range was 0.01 - 2 microg mL(-1) simetryn with a correlation coefficient (r(2)) of 0.9997 and relative standard deviations (RSD; n = 4) in the range of 0.9 - 2.3%. The limit of detection (S/N = 3) was 7.5 ng mL(-1) with a sample throughput of 100 h(-1). The proposed method has been applied to determine simetryn in natural waters using Sep-Pak C(18) cartridges for solid phase extraction (SPE) procedure. The recoveries were in the range of 97 +/- 1 to 104 +/- 2%. The mechanism of chemiluminescence reaction has also been discussed briefly. 相似文献
18.
19.
Ishan Barman Narahara Chari Dingari Gajendra Pratap Singh Rajesh Kumar Stephen Lang Ghulam Nabi 《Analytical and bioanalytical chemistry》2012,404(10):3091-3099
In recent years, Raman spectroscopy has shown substantive promise in diagnosing bladder cancer, especially due to its exquisite molecular specificity. The ability to reduce false detection rates in comparison to existing diagnostic tools such as photodynamic diagnosis makes Raman spectroscopy particularly attractive as a complementary diagnostic tool for real-time guidance of transurethral resection of bladder tumor (TURBT). Nevertheless, the state-of-the-art high-volume Raman spectroscopic probes have not reached the expected levels of specificity thereby impeding their clinical translation. To address this issue, we propose the use of a confocal Raman probe for bladder cancer diagnosis that can boost the specificity of the diagnostic algorithm based on its suppression of the out-of-focus non-analyte-specific signals emanating from the neighboring normal tissue. In this article, we engineer and apply such a probe, having depth of field of approximately 280?μm, for Raman spectral acquisition from ex vivo normal and cancerous TURBT samples. Using this clinical dataset, a diagnostic algorithm based on principal component analysis and logistic regression is developed. We demonstrate that this approach results in comparable sensitivity but significantly higher specificity in relation to high-volume Raman spectral data. The application of only two principal components is sufficient for the discrimination of the samples underlining the robustness of the algorithm. Further, no discordance between replicate spectra is observed emphasizing the reproducible nature of the current diagnostic assessment. The high levels of sensitivity and specificity achieved in this proof-of-concept study opens substantive avenues for application of a confocal Raman probe during endoscopic procedures related to diagnosis and treatment of bladder cancer. Figure
Artistic depiction of the working principle of the confocal Raman spectroscopic sensor for urinary bladder cancer diagnosis 相似文献
20.
A flow injection method is described for the determination of iron in fresh water based on potassium permanganate chemiluminescence
detection via oxidation of formaldehyde in aqueous hydrochloric acid. Total iron concentrations are determined after reducing
Fe(III) to Fe(II) using hydroxylamine hydrochloride. The detection limit (three standard deviations of blank) is 1.0 nM, with
a sample throughput of 120 h−1. The calibration graph was linear over the range (2–10) × 10−7 M (r
2 = 0.9985) with relative standard deviations (n = 5) in the range 1.0–2.3%. The effect of interfering cations (Ca(II), Mg(II), Zn(II), Ni(II), Co(II), Fe(III), Mn(II), Pb(II),
and Cu(II)) and common anions (Cl−, SO
4
2−
, PO
4
3−
, NO
3
−
, NO
2
−
, I−, F−, and SO
3
2−
) was studied at their maximum admissible concentrations in fresh water. The method was applied to fresh-water samples from
the Quetta Valley, and the results obtained (0.04 ± 0.001–0.11 ± 0.01 mg/L Fe(II)) were in reasonable agreement with those
obtained using the spectrophotometric reference method (0.05 ± 0.01–0.12 ± 0.02 mg/L Fe(II)).
The text was submitted by the authors in English. 相似文献