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991.
Dr. Masaki Yoshida Hotaka Shitama Dr. W. M. C. Sameera Dr. Atsushi Kobayashi Prof. Dr. Masako Kato 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(32):7669-7678
An electrochromic system showing ease of color tunability has been constructed using a triple-decker PtII complex [Pt3(μ3-pydt)2(bpy)3]2+ (H2pydt=2,6-pyridinedithiol, bpy=2,2′-bipyridine). The divalent complex undergoes electrochemically quasi-reversible two-electron transfer coupled with the coordination/dissociation of axial ligands, forming higher valent Pt(+2.67) species [Pt3X2(μ3-pydt)2(bpy)3]2+ (X=Cl−, Br−, and SCN−). These higher valent species exhibit characteristic colors ranging from red to cyan depending on the counter anion X− of the electrolyte. The triple-decker structure provides a novel multicolor electrochromic system with favorable stability and reversibility. Theoretical calculations indicate that the colors of the Pt(+2.67) species are tunable by the trans influence of the axial ligand X−. This novel strategy of post-synthetic color-tuning using triplatinum systems should enable the facile preparation of colorful electrochromic devices without any complicated procedures, which may find application in flexible displays, optical devices, and sensors. 相似文献
992.
Takashi Doi Tsutomu Shimokawa Atsushi Sudo Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2019,57(4):531-538
This article presents the effect of some ionic photochemical acid generators (PAGs) to inhibit the dissolution of hexafluoroisopropylalcohol (HFA)‐containing polystyrene to an aqueous alkaline developer, which is a highly important effect in photoresist application to enhance resolution of patterning. The dissolution inhibiting factors and mechanisms were investigated by evaluating the solubility and the 1H‐NMR analysis of OH proton in HFA moiety. The dissolution inhibition effect was enhanced when the structures of PAGs fulfill some requirements: (a) their anions should have higher basicity and smaller van der Waals volume; (b) their cations should be stabilized by conjugation with electron‐rich aromatics. In the dissolution inhibition, the HFA moiety interacts with the anionic part of PAGs liberated from the electrostatic interaction with the counter cation. These interactions were predicted and quantified by DFT calculations using Gaussian 09, leading to the rational designs of PAGs with higher dissolution inhibiting effect in photoresist systems. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 531–538 相似文献
993.
Shusuke Okamoto Atsushi Sudo Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2019,57(16):1723-1729
Radical ring‐opening polymerization of 1,1‐dicyano‐2‐vinylcyclopropane 1 was performed in benzonitrile to find the corresponding homopolymer 2 soluble in organic solvents was successfully obtained while that in other solvents gave crosslinked and thus insoluble homopolymer. In addition, 1 underwent radical copolymerization with 1‐cyano‐1‐ester‐2‐vinylcyclopropanes 3 and 4 to afford the corresponding copolymers 7 and 8 . By increasing the content of the 1 ‐derived unit in the resulting copolymers, the solubility of the copolymers in organic solvents became lower and the residual weights at 600 °C and their glass transition temperatures became higher. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1723–1729 相似文献
994.
Yasuyuki Mori Atsushi Sudo Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2019,57(14):1564-1568
Oligo(spiroorthocarbonate)s 1 , which were synthesized by the polycondensation of pentaerythritol derivatives with tetraethylorthocarbonate, were employed as comonomers in the cationic polymerization of epoxide initiated by sulfonium salt. In the copolymerization, the spiroorthocarbonate moiety of 1 underwent double ring‐opening reaction, leading to the efficient diminution of the volume shrinkage upon the copolymerization. Thermal properties of the resulting networked polymers were evaluated by TGA. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1564–1568 相似文献
995.
Akira Takahashi Ryu Yuzaki Yoshihito Ishida Atsushi Kameyama 《Journal of polymer science. Part A, Polymer chemistry》2019,57(24):2442-2449
Ring‐expansion polymerization (REP) of thiiranes was investigated using 3H‐benzothiazol‐2‐one (BT) as the cyclic aromatic thiourethane initiator in the presence of tetrabutylammonium chloride (TBAC) catalyst. The polymerization proceeded in a well‐controlled manner to afford cyclic polysulfides with one BT moiety per macrocycle, as confirmed by MALDI‐TOF MS spectroscopy. Differential scanning calorimetry (DSC) measurement of the obtained cyclic polysulfides revealed slight decrease in the glass‐transition temperature as the increase in the molecular weight, supporting the cyclic topology of the products. Postpolymerization of thiiranes using the BT‐initiated cyclic polysulfide as the macroinitiator afforded the ring‐expanded product while maintaining the narrow polydispersity and well‐defined cyclic structure, which enabled precise synthesis of cyclic block copolymer with different thiirane combination. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2442–2449 相似文献
996.
Kojima Chie Watanabe Kenji Murata Hidenobu Nishio Yuki Makiura Rie Matsunaga Katsuyuki Nakahira Atsushi 《Research on Chemical Intermediates》2019,45(1):23-32
Research on Chemical Intermediates - Hydroxyapatite (HA) is a biocompatible and porous material that is useful for gene delivery. In this study, various Zn- and Mg-doped HA samples were produced by... 相似文献
997.
Keigo Matsuyama Akito Fukui Kohei Miura Hisashi Ichimiya Yuki Aoki Yuki Yamada Prof. Atsushi Ashida Prof. Takeshi Yoshimura Prof. Norifumi Fujimura Prof. Daisuke Kiriya 《ChemistryOpen》2019,8(7):908-914
Transition metal dichalcogenides (TMDCs) have received attention as atomically thin post-silicon semiconducting materials. Tuning the carrier concentrations of the TMDCs is important, but their thin structure requires a non-destructive modulation method. Recently, a surface-charge transfer doping method was developed based on contacting molecules on TMDCs, and the method succeeded in achieving a large modulation of the electronic structures. The successful dopant is a neutral benzyl viologen (BV0); however, the problem remains of how to effectively prepare the BV0 molecules. A reduction process with NaBH4 in water has been proposed as a preparation method, but the NaBH4 simultaneously reacts vigorously with the water. Here, a simple method is developed, in which the reaction vial is placed on a hotplate and a fragment of air-stable metal is used instead of NaBH4 to prepare the BV0 dopant molecules. The prepared BV0 molecules show a strong doping ability in terms of achieving a degenerate situation of a TMDC, MoS2. A key finding in this preparation method is that a convection flow in the vial effectively transports the produced BV0 to a collection solvent. This method is simple and safe and facilitates the tuning of the optoelectronic properties of nanomaterials by the easily-handled dopant molecules. 相似文献
998.
999.
Toyoshima Atsushi Mitsukai Akina Tsukada Kazuaki Ooe Kazuhiro Haba Hiromitsu Komori Yukiko Murakami Masashi Kaneya Yusuke Sato Daisuke Asai Masato Sato Tetsuya K. Nagame Yuichiro 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):421-430
Journal of Radioanalytical and Nuclear Chemistry - We have studied extraction behavior of group-6 elements Mo and W to search for suitable conditions for an on-line extraction experiment of their... 相似文献
1000.