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101.
102.
Makio Iwahashi Tadashi Nozaki Kazuyuki Kamaya Kenichi Taguchi Masahiro Fujita Yasutoshi Kasahara Hideyuki Minami Hideyo Matsuzawa Shinji Nakamura Katsuyoshi Harada Yukihiro Ozaki Tohru Inoue 《The Journal of chemical thermodynamics》2011,43(1):80-87
Phase behaviors of the binary mixtures composed of ethylene carbonate (EC) and aliphatic alcohols, ω-phenyl alcohols, and alkylbenzenes were investigated. In addition, heat of solution of EC into these organic solvents was measured. The EC/methanol and EC/ethanol systems gave homogeneous solution at the temperature above their liquidus lines, while the mixtures of EC and alcohols with longer alkyl chain showed a miscibility gap in a liquid phase and provided the monotectic-type phase diagram. The liquid–liquid phase separation region expanded with the increase in the alkyl chain length. A similar phase behavior was also observed for the mixtures of EC and alkylbenzenes. On the other hand, the EC mixtures with ω-phenyl alcohols showed no miscibility gap in a liquid phase at least up to 4-phenylbutan-1-ol which has C4 alkyl chain intervening between phenyl and hydroxyl groups. This result demonstrates that both of the hydroxyl and phenyl groups act to facilitate the mixing of aliphatic compounds with EC. The phase behavior of these EC mixtures was analyzed applying the modified regular solution model in which the pair interaction energy was regarded as free energy. The model calculation with the use of heat of solution of EC at infinite dilution as the pair interaction enthalpy reproduced well both of the experimentally obtained liquidus line and mutual solubility curve as well as monotectic point. 相似文献
103.
Takahashi H Wakamatsu S Tabata H Oshitari T Harada A Inoue K Natsugari H 《Organic letters》2011,13(4):760-763
To elucidate the active conformation of indometacin that differentiates between cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2), the stereochemistry around the N-benzoylated indole moiety of indometacin was studied. Resolution of stable atropisomers as representative conformations was found to be possible by restricting rotation about the N-C7' and/or C7'-C1' bond. Only the aR-isomer showed specific inhibition of COX-1, and COX-2 was not inhibited by either atropisomer. 相似文献
104.
An efficient route toward the central ABC system of jiadifenin has been developed using two key Pd-catalyzed cyclizations. A protic solvent-activated Mizoroki-Heck reaction was used to construct the C(9) quaternary carbon and the A ring. A cascading Tsuji-Trost cyclization/lactonization sequence was employed to establish the BC ring system and the C(5,6) stereochemistry. 相似文献
105.
Sakamoto K Takashima Y Hamada N Ichida H Yamaguchi H Yamamoto H Harada A 《Organic letters》2011,13(4):672-675
An energy transfer process was investigated using cyclodextrin-oligothiophene rotaxanes (2T-[2]rotaxane). The excited energy of 2T-[2]rotaxane is transferred to the sexithiophene derivative which is included in the cavity of β-CD stoppers of 2T-[2]rotaxane. 相似文献
106.
Harada T Nakagawa Y Ogura T Yamada Y Ohe T Miyagawa H 《Journal of chemical information and modeling》2011,51(2):296-305
Insect growth is regulated by the orchestrated event of ecdysteroids and their receptor proteins. Agonists/antagonists of ecdysteroid receptor are predicted to disrupt normal growth, providing good candidates of new insecticides. A database of over 2 million compounds was subjected to a shape-based virtual screening cascade to identify novel nonsteroidal hits similar to the known EcR ligand ponasterone A. Testing revealed micromolar hits against two strains of insect cells. Docking experiments against EcR were used to support the predicted binding mode of these ligands based on their overlay to ponasterone A. 相似文献
107.
We present an effective method for estimating the motion of proteins from the motion of attached probe particles in single-molecule experiments. The framework naturally incorporates Langevin dynamics to compute the most probable trajectory of the protein. By using a perturbation expansion technique, we achieve computational costs more than 3 orders of magnitude smaller than the conventional gradient descent method without loss of simplicity in the computation algorithm. We present illustrative applications of the method using simple models of single-molecule experiments and confirm that the proposed method yields reasonable and stable estimates of the hidden motion in a highly efficient manner. 相似文献
108.
IR-dip spectra of trans-acetanilide-water 1:1 cluster, AA-(H(2)O)(1), have been measured for the S(0) and D(0) state in the gas phase. Two structural isomers, where a water molecule binds to the NH group or the CO group of AA, AA(NH)-(H(2)O)(1) and AA(CO)-(H(2)O)(1), are identified in the S(0) state. One-color resonance-enhanced two-photon ionization, (1 + 1) RE2PI, of AA(NH)-(H(2)O)(1) via the S(1)-S(0) origin generates [AA(NH)-(H(2)O)(1)](+) in the D(0) state, however, photoionization of [AA(CO)-(H(2)O)(1)] does not produce [AA(CO)-(H(2)O)(1)](+), leading to [AA(NH)-(H(2)O)(1)](+). This observation explicitly indicates that the water molecule in [AA-(H(2)O)(1)](+) migrates from the CO group to the NH group in the D(0) state. The reorganization of the charge distribution from the neutral to the D(0) state of AA induces the repulsive force between the water molecule and the CO group of AA(+), which is the trigger of the water migration in [AA-(H(2)O)(1)](+). 相似文献
109.
110.
Noriaki Nishiguchi Takafumi Kinuta Yoko Nakano Dr. Takunori Harada Dr. Nobuo Tajima Tomohiro Sato Prof. Dr. Michiya Fujiki Prof. Dr. Reiko Kuroda Prof. Dr. Yoshio Matsubara Dr. Yoshitane Imai 《化学:亚洲杂志》2011,6(4):1092-1098
The solid‐state chiral optical properties of a 4‐(2‐arylethynyl)‐benzoic acid/amine supramolecular organic fluorophore can be controlled by changing the arylethynyl group of the achiral 4‐(2‐arylethynyl)‐benzoic acid component molecule rather than the chirality of the amine component molecule. 相似文献