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671.
Targeted Ultrasound‐Assisted Cancer‐Selective Chemical Labeling and Subsequent Cancer Imaging using Click Chemistry 下载免费PDF全文
Hua Wang Marianne Gauthier Jamie R. Kelly Rita J. Miller Ming Xu Prof. Dr. William D. O'Brien Jr. Prof. Dr. Jianjun Cheng 《Angewandte Chemie (International ed. in English)》2016,55(18):5452-5456
Metabolic sugar labeling followed by the use of reagent‐free click chemistry is an established technique for in vitro cell targeting. However, selective metabolic labeling of the target tissues in vivo remains a challenge to overcome, which has prohibited the use of this technique for targeted in vivo applications. Herein, we report the use of targeted ultrasound pulses to induce the release of tetraacetyl N‐azidoacetylmannosamine (Ac4ManAz) from microbubbles (MBs) and its metabolic expression in the cancer area. Ac4ManAz‐loaded MBs showed great stability under physiological conditions, but rapidly collapsed in the presence of tumor‐localized ultrasound pulses. The released Ac4ManAz from MBs was able to label 4T1 tumor cells with azido groups and significantly improved the tumor accumulation of dibenzocyclooctyne (DBCO)‐Cy5 by subsequent click chemistry. We demonstrated for the first time that Ac4ManAz‐loaded MBs coupled with the use of targeted ultrasound could be a simple but powerful tool for in vivo cancer‐selective labeling and targeted cancer therapies. 相似文献
672.
Spectroscopic and Computational Characterization of Diethylenetriaminepentaacetic Acid/Transplutonium Chelates: Evidencing Heterogeneity in the Heavy Actinide(III) Series 下载免费PDF全文
Dr. Gauthier J.‐P. Deblonde Dr. Morgan P. Kelley Dr. Jing Su Dr. Enrique R. Batista Dr. Ping Yang Dr. Corwin H. Booth Prof. Rebecca J. Abergel 《Angewandte Chemie (International ed. in English)》2018,57(17):4521-4526
The chemistry of trivalent transplutonium ions (Am3+, Cm3+, Bk3+, Cf3+, Es3+…) is usually perceived as monotonic and paralleling that of the trivalent lanthanide series. Herein, we present the first extended X‐ray absorption fine structure (EXAFS) study performed on a series of aqueous heavy actinide chelates, extending past Cm. The results obtained on diethylenetriaminepentaacetic acid (DTPA) complexes of trivalent Am, Cm, Bk, and Cf show a break to much shorter metal–oxygen nearest‐neighbor bond lengths in the case of Cf3+. Corroborating those results, density functional theory calculations, extended to Es3+, suggest that the shorter Cf?O and Es?O bonds could arise from the departure of the coordinated water molecule and contraction of the ligand around the metal relative to the other [MIIIDTPA(H2O)]2? (M=Am, Cm, Bk) complexes. Taken together, these experimental and theoretical results demonstrate inhomogeneity within the trivalent transplutonium series that has been insinuated and debated in recent years, and that may also be leveraged for future nuclear waste reprocessing technologies. 相似文献
673.
R.Gobin P-Y.Beauvais A.Ben Ismail D.Bogard O.Delferriere D.De Menezes R.Duperrier Y.Gauthier F.Harrault P-A.Leroy O.Tuske D.Uriot 《中国物理 C》2007,31(Z1):46-50
In the beginning of the 90s,T.Taylor and his collaborators demonstrated ECR sources operating at low frequency(i.e.2.45GHz)are able to produce very intense single charge light ion beams. At CEA/Saclay,the SILHI source developments started in 1995.Since 1997 more than 100mA proton or deuteron beams are routinely produced in pulsed or continuous mode.To comply with ADS reliability constraint,important improvements have been performed to increase the installation reliability.Moreover,to optimize the beam transport in the low energy beam line,the extraction system was carefully designed and space charge compensation studies were undertaken.An important step has been reached in 2005 with the development of a permanent magnet source able to produce a total beam of 109mA at 85kV. A new test bench named BETSI,especially dedicated to permanent magnet source developments,is presently under construction.It will allow analysing positive or negative extracted beams up to 50keV and 100mA. In addition,for several years work has been done to optimize the production of negative hydrogen ion beam with such an ECR source.Recent analysis pushed towards the construction of a new set up based on a multicusp magnetic configuration. After a brief overview of the CEA/Saclay source developments,this article will point out on the recent results and present status. 相似文献
674.
Gauthier S Solari E Dutta B Scopelliti R Severin K 《Chemical communications (Cambridge, England)》2007,(18):1837-1839
The reaction of RuCl(3)(solv.)(n) with tert-butylacetylene in methanol or ethanol leads to the formation of chloro-bridged half-sandwich complexes with sterically demanding cyclopentadienyl ligands, which are of high interest as starting materials for the synthesis of novel Ru catalysts. 相似文献
675.
Jerzy Krasinski Daniel J. Gauthier Michelle S. Malcuit Robert W. Boyd 《Optics Communications》1985,54(4):241-245
A two-photon resonantly enhanced four-wave mixing (FWM) process leading to the conical emission of two new frequency components has been observed in atomic sodium vapor. A dye laser tuned close to the 3s → 3d two-photon allowed transition produces broad-band emission near the frequencies of the 3d → 3p and 3p → 3s transitions. This radiation is emitted in the forward direction in the form of cones surrounding the transmitted laser beam. The dependence of the cone angle on the emission wavelength and atomic number density is in excellent agreement with the predictions of a model that ascribes the origin of the conical emission to a phase-matched four-wave mixing process. 相似文献
676.
We demonstrate a position-sensing technique that relies on the inherent sensitivity of chaos, where we illuminate a subwavelength object with a complex structured radio-frequency field generated using wave chaos and nonlinear feedback. We operate the system in a quasiperiodic state and analyze changes in the frequency content of the scalar voltage signal in the feedback loop. This allows us to extract the object's position with a one-dimensional resolution of ~λ/10,000 and a two-dimensional resolution of ~λ/300, where λ is the shortest wavelength of the illuminating source. 相似文献
677.
The molecular structures of gaseous tetrafluoro-p-benzoquinone (p-fluoranil) and tetramethyl-p-benzoquinone (duroquinone) have been investigated by electron diffraction. Except for the methyl group hydrogen atoms, the molecules are planar to within experimental error, but small deviations from planarity are completely compatible with the data. Values for the geometrical parameters (radistances and rα with parenthesized uncertainties of 2σ including estimated uncertainty in the electron wavelength and correlation effects, are as follows. Tetrafluoro-p-benzoquinone: D2h symmetry (assumed); r(C0) = 1.211(6) Å, r(CC) = 1.339(12) Å, r(C-C) = 1.489(5') Å, r(C-F) = 1.323(5) Å, ∠C-C-C = 116.8(7)° and ∠C-C-F = 116.1(7)°. Tetramethyl-p-benzoquinone: C2h symmetry (assumed);r(C-H) = 1.102(18) Å, r(CO) = 1.229(8) Å, r(CC) = 1.352(8) Å, r(Csp2-Csp2) = 1.491(11) Å, r(Csp2-Csp3) = 1.504(12) A, ∠C-CO-C = 120.8(8)°. ∠C-C-CH3 = 116.1(8)°, ∠C-C-H = 110.5(34)° and α1 = α2 (methyl torsion = 30° (assumed). 相似文献
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