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排序方式: 共有279条查询结果,搜索用时 15 毫秒
271.
Hsiung LC Chiang CL Wang CH Huang YH Kuo CT Cheng JY Lin CH Wu V Chou HY Jong DS Lee H Wo AM 《Lab on a chip》2011,11(14):2333-2342
We present a dielectrophoresis (DEP)-based cellular microarray chip for cell-based anticancer drug screening in perfusion microenvironments. Human breast cancer cells, MCF7, were seeded into the chip and patterned via DEP forces onto the planar interdigitated ring electrode (PIRE) arrays. Roughly, only one third of the cell amount was required for the chip compared to that for a 96-well plate control. Drug concentrations (cisplatin or docetaxel) were stably generated by functional integration of a concentration gradient generator (CGG) and an anti-crosstalk valve (ACV) to treat cells for 24 hours. Cell viability was quantified using a dual staining method. Results of cell patterning show substantial uniformity of patterned cells (92 ± 5 cells per PIRE). Furthermore, after 24 hour drug perfusion, no statistical significance in dose-responses between the chip and the 96-well plate controls was found. The IC(50) value from the chip also concurred with the values from the literature. Moreover, the perfusion culture exhibited reproducibility of drug responses of cells on different PIREs in the same chamber. The chip would enable applications where cells are of limited supply, and supplement microfluidic perfusion cultures for clinical practices. 相似文献
272.
Bhardwaj V Trabelsi K Singh JB Choi SK Olsen SL Adachi I Adamczyk K Asner DM Aulchenko V Aushev T Aziz T Bakich AM Barberio E Belous K Bhuyan B Bischofberger M Bondar A Bračko M Brodzicka J Browder TE Chen A Chen P Cheon BG Cho K Choi Y Dalseno J Doležal Z Eidelman S Epifanov D Gaur V Gabyshev N Golob B Haba J Hayasaka K Hayashii H Horii Y Hoshi Y Hou WS Hsiung YB Hyun HJ Iijima T Inami K Ishikawa A Iwabuchi M Iwasaki Y Iwashita T Joshi NJ Julius T Kang JH Kawasaki T Kiesling C Kim HO Kim JB 《Physical review letters》2011,107(9):091803
We report a study of B→(J/ψγ)K and B→(ψ'γ)K decay modes using 772×10? B ?B events collected at the Υ(4S) resonance with the Belle detector at the KEKB energy-asymmetric e(+)e(-) collider. We observe X(3872)→J/ψγ and report the first evidence for χ(c2)→J/ψγ in B→(X_{c ?cγ)K decays, while in a search for X(3872)→ψ'γ no significant signal is found. We measure the branching fractions, B(B(±)→X(3872)K(±))B(X(3872)→J/ψγ)=(1.78(-0.44)(+0.48)±0.12)×10(-6), B(B(±)→χ(c2)K(±))=(1.11(-0.34)(+0.36)±0.09)×10(-5), B(B(±)→X(3872)K(±))B(X(3872)→ψ'γ)<3.45×10? (upper limit at 90% C.L.), and also provide upper limits for other searches. 相似文献
273.
Effects of Core‐modification on Porphyrin Sensitizers to the Efficiencies of Dye‐sensitized Solar Cells
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Sandeep B. Mane Liyang Luo Gao‐Fong Chang Eric Wei‐Guang Diau Chen‐Hsiung Hung 《中国化学会会志》2014,61(5):545-555
To study dye‐sensitized solar cells (DSSCs) with core‐modified porphyrins as the sensitizing dyes, three porphyrins with an ethynyl benzoic acid as an anchoring group are prepared. The properties of free‐base regular porphyrin (N4), thiaporphyrin (N3S) and oxaporphyrin (N3O) were thoroughly studied by spectroscopic methods, DFT calculations, and photovoltaic measurements. Replacing one of the porphyrinic core nitrogen atoms by oxygen or sulfur considerably changes the absorption spectra. The Soret band of the N3O and N3S observed bathochromic shifts of 3‐9 nm while the Q band reaches 700 nm to the near‐infrared region. The overall conversion efficiencies of the DSSCs based on these porphyrins are in the order N4 (3.66%) ? N3S (0.22%) > N3O (0.01%). The time‐correlated single photon counting observed short fluorescence lifetimes for N3O adsorbed both on TiO2 and Al2O3 which explicates the poor efficiency of DSSC using N3O as the photosensitizer. 相似文献
274.
H. Abd. Mohamed Chin‐Lin Hsieh Chin Hsu Ching‐Chuan Kuo Hsuan‐Shuo Chang Ching‐Kuo Lee Tzon‐Huei Lee Jin‐Bin Wu Chi‐I Chang Yueh‐Hsiung Kuo 《Helvetica chimica acta》2014,97(8):1146-1151
A new abietane diterpene, named abietopinoic acid, and a new podocarpane diterpene, named podopinoic acid, were isolated from the acetone extract of the heartwood of Pinus massoniana. Their structures were established as 12‐hydroxy‐7‐oxoabieta‐8,11,13‐trien‐18‐oic acid ( 1 ) and 13‐hydroxy‐7‐oxopodocarpane ( 2 ) by means of spectroscopic analyses including 2D‐NMR. To the best of our knowledge, this is the second report of a podocarpa‐8,11,13‐trien‐18‐oic acid diterpene, isolated from the genus Pinus. 相似文献
275.
Somov A Schwartz AJ Abe K Abe K Adachi I Aihara H Anipko D Arinstein K Asano Y Aulchenko V Aushev T Aziz T Bahinipati S Bakich AM Balagura V Bay A Bedny I Belous K Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang MC Chang P Chao Y Chen A Chen WT Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Cole S Dalseno J Dash M Dragic J Drutskoy A Eidelman S Epifanov D Gabyshev N Garmash A Gershon T Go A Gokhroo G Golob B Hara K Hara T Hastings NC Hayasaka K Hayashii H 《Physical review letters》2006,96(17):171801
We have measured the branching fraction , longitudinal polarization fraction f(L), and CP asymmetry coefficients A and S for B(0) --> rho(+) rho(-) decays with the Belle detector at the KEKB e(+) e(-) collider using 253 Fb(-1) of data. We obtain B = [22.8 +/- 3.8(stat)(+2.3)(-2.6)(syst)] x 10(-6), f(L) = 0.941 (+0.034)(-0.040)(stat) +/- 0.030(syst). A = 0.00 +/- 0.30(stat) +/- 0.09(syst) and S = 0.08 +/- 0.09(syst). These values are used to constrain the Cabibbo-Kobayashi-Maskawa phase ; the solution consistent with the standard model is phi(2) = (88 +/- 17) degrees or 59 degrees < phi(2) < 115 degrees at 90% C.L. 相似文献
276.
Gao‐Fong Chang Anil Kumar Wei‐Min Ching Han‐Wei Chu Chen‐Hsiung Hung Prof. Dr. 《化学:亚洲杂志》2009,4(1):164-173
The condensation reaction of α,α′‐dihydroxy‐1,3‐diisopropylbenzene, pyrrole, and an aldehyde leads to the formation of tetramethyl‐m‐benziporphodimethene and outer α‐pyrrolic carbon oxygenated N‐confused tetramethyl‐m‐benziporphodimethenes containing a γ‐lactam ring in the macrocycle. Two isomers with the carbonyl group of the lactam ring either close to (O‐Up) or away from (O‐Down) the neighboring sp3 meso carbon were synthesized and characterized. The single crystal X‐ray diffraction analysis on the regular and γ‐lactam containing tetramethyl‐m‐benziporphodimethenes showed highly distorted macrocycles for all compounds. For O‐Up and O‐Down isomers, dimeric structures, assembling by intermolecular hydrogen‐bonding interactions through lactam rings, were observed in the solid state. Fitting the concentration dependent chemical shifts of the outer NH proton using the non‐linear regression method give a maximum association constant of 108.9 M ?1 for the meso 4‐methylcarboxyphenyl substituted O‐Down isomer. The DFT calculations concluded that the O‐Up isomer is energetically more stable, and the keto form is more stable than the enol form. 相似文献
277.
An FP Bai JZ Balantekin AB Band HR Beavis D Beriguete W Bishai M Blyth S Boddy K Brown RL Cai B Cao GF Cao J Carr R Chan WT Chang JF Chang Y Chasman C Chen HS Chen HY Chen SJ Chen SM Chen XC Chen XH Chen XS Chen Y Chen YX Cherwinka JJ Chu MC Cummings JP Deng ZY Ding YY Diwan MV Dong L Draeger E Du XF Dwyer DA Edwards WR Ely SR Fang SD Fu JY Fu ZW Ge LQ Ghazikhanian V Gill RL Goett J Gonchar M Gong GH Gong H Gornushkin YA Greenler LS Gu WQ Guan MY Guo XH Hackenburg RW Hahn RL Hans S He M He Q 《Physical review letters》2012,108(17):171803
The Daya Bay Reactor Neutrino Experiment has measured a nonzero value for the neutrino mixing angle θ(13) with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GWth reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With a 43,000 ton-GWth-day live-time exposure in 55 days, 10,416 (80,376) electron-antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to expected number of antineutrinos at the far hall is R=0.940±0.011(stat.)±0.004(syst.). A rate-only analysis finds sin(2)2θ(13)=0.092±0.016(stat.)±0.005(syst.) in a three-neutrino framework. 相似文献
278.
279.