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1.
Computer processing of gas chromatographic data is discussed, with special emphasis on the numerical operations needed. The CHADIC program is described. This program enables optimal separation conditions to be determined and isothermal gas chromatograms to be processed for qualitative and quantitative analysis.  相似文献   
2.
The aim of this work was to optimize our natural hair dyeing system which we described in our previous work and to compare with other dyeing systems. Therefore, we investigated concentration limits of matcha and mordant and compared this new dyeing method with commercial permanent systems on the market. Completely unpigmented hair tresses were dyed with matcha powder (camelia sinensis) and iron(II)-lactate. To investigate the wash fastness and concentration limits, the differently dyed hair tresses were spectrophotometrically measured. The comparison of the damage potential for which cysteic acid is an indicator was measured by NIR. The concentration of matcha and mordant are responsible for the intensity of the color results. The higher the matcha or the mordant concentration, the darker the color results of the dyed hair tresses. Hair damage of matcha mordant dyeing is comparable with results of commercial permanent hair coloration systems. Moreover, the results of wash fastness of matcha mordant dyed hair tresses is comparable and even better by tendency to permanent colored hair tresses.  相似文献   
3.
(Dynamic Interpretation of Infrared Spectra) Results of investigation of an algorithm, based on a novel static-dynamic method, for interpretation of infrared spectra are presented. The IRSCAN-D algorithm can recognize 103 infrared-active substructures comprising C, H, N, O, S, halogen, P and Si atoms. The results indicate that the algorithm is efficient; roughly 97% of the substructures are correctly ascribed, with a surprisingly low number (60%) of false recognition.  相似文献   
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The properties of passive Q-switched short-cavity dye lasers (SCDL) and passive Q-switched distributed-feedback dye lasers (DFDL) are investigated theoretically by using rate-equation models. The calculations, in agreement with experimental results, predict a significant decrease of the pulse energy fluctuation and the pulse duration of both the SCDL and DFDL, when passive Q-switching is used.  相似文献   
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The uncatalyzed and oxalic acid catalyzed modification of polyvinyl alcohol (PVA) with aluminium isopropoxide have been studied for reaction in a suspension of powdered PVA in boiling benzene. Isopropyl alcohol (IPA) formed during the reaction was removed by continuous distillation of an IPA-benzene mixture. The reaction was initially quite fast but slowed up rapidly and practically stopped when only 4–12% of the OH-groups had reacted. Thermogravimetric analysis (TGA) showed that products with 6.8 mole A1/100 mole VA exhibit a significant rise in decomposition temperature from 250 to 285°. The characteristics are attributed to the occurrence of vicinal OH-groups in PVA.  相似文献   
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79Se has been investigated by the reaction76Ge(α, nγ). Gamma excitation functions (E α=10?15 MeV), gamma angular distributions and gamma-gamma coincidences (both at (E α=12 MeV), have been taken. A level scheme has been established, spins and partities have been assigned. The results are compared with rotational bands in neighbouring odd Se isotopes. Nuclear reaction76Ge(α, nγ)E α =12 MeV; measuredE γ,I γ,γ-γ coincidences,γ-angular distribution,γ-excitation function.79Se deduced levels,J, π. Enriched target, Ge(Li).  相似文献   
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The computer program SCANSYNTH is designed to assist in planning organic syntheses. The system features a new mode of data input/output, and is self-adapting, with simultaneous generation of possible synthesis schemes in the forward and reverse directions. Operational options include modeling of individual reactions, one-step reactions and multi-step reactions.  相似文献   
10.
The first general protocol for the preparation of different polymer-bound 1,2-diaza-1,3-butadienes is reported. The utility of these supported reagents in the solid-phase synthesis of 4-triphenylphosphoranylidene-4,5-dihydropyrazol-5-ones by reaction with triphenylphosphine is presented.  相似文献   
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