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31.
A. Sengupta S. K. Thulasidas V. C. Adya P. K. Mohapatra S. V. Godbole V. K. Manchanda 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(3):1017-1023
During the simultaneous extraction of plutonium and uranium using anion exchange chromatographic technique from analytical
waste in hydrochloric acid medium, 241Am which is invariably present in the plutonium bearing fuel samples remains in the effluent. A two step separation scheme
was developed for the recovery and purification of Am from the assorted waste to facilitate the disposal of large volume of
aqueous waste and the purified Am solution was utilized for spectroscopic investigation. The separation scheme involved solvent
extraction using 0.1 M TODGA + 0.5 M DHOA for separation of americium from Fe, Pb, Ni and Na followed by extraction chromatographic
technique using CMPO on inert support as stationary phase for separation of Ca from Am. A systematic study on the extraction
behavior of Am from hydrochloric acid medium revealed that out of four extraction systems well known for actinide partitioning
namely 0.1 M TODGA + 0.5 M DHOA, 1 M DMDBTDMA, 0.2 M CMPO + 1.2 M TBP and 30% TRPO, only 0.1 M TODGA + 0.5 M DHOA extracts
americium from 7.5 M HCl feed acidity. A comparative study involving CMPO solvent extraction and column chromatographic technique
revealed that elution of Am from column is satisfactory as compared to inefficient stripping of Am from organic phase in solvent
extraction technique using 0.1 M HNO3. The purity of the final solution was checked for 17 elements of interest and was found to be 98% pure, while the overall
recovery of this two step separation scheme was found to be 95%. 相似文献
32.
Experimental Techniques - The conventional photoelastic method of stress freezing could not be employed for analysis of a Francis runner blade under hydraulic loading. The impasse was overcome by a... 相似文献
33.
34.
K. Venugopal Chetty A. G. Godbole R. Swarup V. N. Vaidya V. Venugopal P. R. Vasudeva Rao 《Journal of Radioanalytical and Nuclear Chemistry》2005,267(1):125-130
Summary Piroxicam was labeled effectively with 99mTc due to the presence of electron donating atoms such as sulfur, nitrogen, and oxygen in its structure. The labeling yield was found to be influenced by different factors such as the amount of piroxicam, stannous chloride dihydrate, pH of the reaction mixture, reaction time and reaction temperature. The suitable amount of stannous chloride dihydrate required to produce high labeling yield of 99mTc-piroxicam was 50 μg, above this quantity (200 μg) a colloidal solution was formed. Another factor which plays a significant role in this labeling reaction is the pH of the reaction medium. The labeling reaction was done only at alkaline pH range from 9-11, because piroxicam was not soluble at acidic or neutral pH. The labeling reaction proceeded well at room temperature and the complex was decomposed by heat. The labeled piroxicam (99mTc-piroxicam ) showed good localization in inflamed foci and good imaging must be taken at 24-hour post injection, as the ratio of both types of inflammation (sterile and septic) to the background are 10.6 and 8.7, respectively. 相似文献
35.
Z. Leppert Z. Majewska K. Ho C. S. Wan S. H. Wen F. W. Cheng G. Lunde F. Stiebel L. M. Labaune A. Jermakow W. Leithe F. Fritz W. F. Geddes F. H. Lehberg A. Afanassjew M. Podolskaja M. Sserga K. Höll E. Delvaux N. N. Godbole A. M. Se P. S. Varma G. M. Garde M. Procopio H. Levin Alma Tomingas M. E. Marks C. H. Lea G. S. Fawcett F. M. Biffen und F. D. Snell 《Fresenius' Journal of Analytical Chemistry》1938,113(5-6):235-240
Ohne Zusammenfassung 相似文献
36.
We discuss various reactions at futuree
+
e
– and colliders involving real (beamstrahlung or backscattered laser) or quasi-real (bremsstrahlung) photons in the initial state and hadrons in the final state. The production of two central jets with large transverse momentump
T
is described in some detail; we give distributions for the rapidity andp
T
of the jets as well as the di-jet invariant mass, and discuss the relative importance of various initial state configurations and the uncertainties that arise from the at present rather poor knowledge of the parton content of the photon. We also present results for mono-jet production where one jet goes down a beam pipe, for the production of charm, bottom and top quarks, and for single production ofW andZ bosons. Where appropriate, the two-photon processes are compared with annihilation reactions leading to similar final states. We also argue that the behaviour of the total inelastic cross section at high energies will probably have little impact on the severity of background problems caused by soft and semi-hard (minijet) two-photon reactions. We find very large differences in cross sections for all two-photon processes between existing desings for futuree
+
e
– colliders, due to the different beamstrahlung spectra; in particular, both designs with 1 and 1 events per bunch crossing exist. The number of hadronic two-photon events is expected to rise quickly with the beam energy. Hadronic backgrounds will be even worse if thee
+
e
– collider is converted into a collider. 相似文献
37.
38.
R. M. Godbole A. Grau G. Pancheri Y. N. Srivastava 《The European Physical Journal C - Particles and Fields》2009,63(1):69-85
In this paper we apply to the photoproduction total cross section a model we have proposed for purely hadronic processes and
which is based on QCD mini-jets and soft gluon re-summation. We compare the predictions of our model with the HERA data as
well as with other models. For cosmic rays, our model predicts substantially higher cross sections at TeV energies than models
based on factorization, but lower than models based on mini-jets alone, without soft gluons. We discuss the origin of this
difference. 相似文献
39.
An efficient synthesis of naturally occurring and biologically active furonaphthoquinones is described starting from suitably substituted dihydronaphthofuraps. 相似文献
40.
Anna Celaya Anant P. Godbole Mandy Rae Schleifer 《Methodology and Computing in Applied Probability》2006,8(3):357-371
The classical Erdős–Ko–Rado (EKR) Theorem states that if we choose a family of subsets, each of size k, from a fixed set of size
, then the largest possible pairwise intersecting family has size
. We consider the probability that a randomly selected family of size t=t
n
has the EKR property (pairwise nonempty intersection) as n and k=k
n
tend to infinity, the latter at a specific rate. As t gets large, the EKR property is less likely to occur, while as t gets smaller, the EKR property is satisfied with high probability. We derive the threshold value for t using Janson’s inequality. Using the Stein–Chen method we show that the distribution of X
0, defined as the number of disjoint pairs of subsets in our family, can be approximated by a Poisson distribution. We extend
our results to yield similar conclusions for X
i
, the number of pairs of subsets that overlap in exactly i elements. Finally, we show that the joint distribution (X
0, X
1, ..., X
b
) can be approximated by a multidimensional Poisson vector with independent components.
相似文献