全文获取类型
收费全文 | 240篇 |
免费 | 20篇 |
国内免费 | 2篇 |
专业分类
化学 | 202篇 |
数学 | 9篇 |
物理学 | 51篇 |
出版年
2024年 | 4篇 |
2023年 | 4篇 |
2022年 | 3篇 |
2021年 | 11篇 |
2020年 | 14篇 |
2019年 | 4篇 |
2018年 | 10篇 |
2017年 | 4篇 |
2016年 | 11篇 |
2015年 | 5篇 |
2014年 | 13篇 |
2013年 | 13篇 |
2012年 | 25篇 |
2011年 | 19篇 |
2010年 | 7篇 |
2009年 | 7篇 |
2008年 | 16篇 |
2007年 | 12篇 |
2006年 | 10篇 |
2005年 | 5篇 |
2004年 | 7篇 |
2003年 | 10篇 |
2002年 | 1篇 |
2001年 | 7篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 4篇 |
1995年 | 1篇 |
1994年 | 6篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1991年 | 5篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1984年 | 4篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
排序方式: 共有262条查询结果,搜索用时 15 毫秒
131.
Yuto Enomoto Dr. Motofusa Akiyama Dr. Yoshitsugu Morita Prof. Dr. Teruyuki Komatsu 《化学:亚洲杂志》2021,16(24):4057-4061
Anticancer agent doxorubicin-loaded liposomes (DoxLs) were drawn spontaneously into nanotubes comprising multilayers of polyelectrolytes and gold nanoparticles (PAuNTs). We describe a unique structure of PAuNTs incorporating DoxLs (DoxL-PAuNT). The number of DoxLs adsorbed on the tube interior surface was ascertained as 2.4×103. Heating stimuli engendered gel-liquid crystal phase transition of DoxL in the capillary, subsequently inducing efficient release of Dox without structural changes of the tubule or liposome. Furthermore, antitumor activity of the DoxL-PAuNTs on cancer cells was elucidated. 相似文献
132.
Yuto Miyatake 《BIT Numerical Mathematics》2014,54(3):777-799
Recently, the symplectic exponentially-fitted methods for Hamiltonian systems with periodic or oscillatory solutions have been attracting a lot of interest. As an alternative to them, in this paper, we propose a class of energy-preserving exponentially-fitted methods. For this aim, we show sufficient conditions for energy-preservation in terms of the coefficients of continuous stage Runge–Kutta (RK) methods, and extend the theory of exponentially-fitted RK methods in the context of continuous stage RK methods. Then by combining these two theories, we derive second and fourth order energy-preserving exponentially-fitted schemes. 相似文献
133.
M Sato H Yamataka Y Komeiji Y Mochizuki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(31):9714-9721
Full-quantum mechanical fragment molecular orbital-based molecular dynamics (FMO-MD) simulations were applied to the hydration reaction of formaldehyde in water solution under neutral conditions. Two mechanisms, a concerted and a stepwise one, were considered with respect to the nucleophilic addition and the proton transfer. Preliminary molecular orbital calculations by means of polarized continuum model reaction field predicted that the hydration prefers a concerted mechanism. Because the calculated activation barriers were too high for free FMO-MD simulations to give reactive trajectories spontaneously, a More O'Ferrall-Jencks-type diagram was constructed from the statistical analysis of the FMO-MD simulations with constraint dynamics. The diagram showed that the hydration proceeds through a zwitterionic-like (ZW-like) structure. The free energy changes along the reaction coordinate calculated by means of the blue moon ensemble for the hydration and the amination of formaldehyde indicated that the hydration proceeds through a concerted process through the ZW-like structure, whereas the amination goes through a stepwise mechanism with a ZW intermediate. In inspection of the FMO-MD trajectories, water-mediated cyclic proton transfers were observed in both reactions on the way from the ZW-like structure to the product. These proton transfers also have an asynchronous character, in which deprotonation from the nucleophilic oxygen atom (or nitrogen atom for amination) precedes the protonation of the carbonyl oxygen atom. The results showed the strong advantage of the FMO-MD simulations to obtain detailed information at a molecular level for solution reactions. 相似文献
134.
Prof. Dr. Yoshihiro Matano Arihiro Saito Yuto Suzuki Tooru Miyajima Seiji Akiyama Dr. Saika Otsubo Emi Nakamoto Dr. Shinji Aramaki Prof. Dr. Hiroshi Imahori 《化学:亚洲杂志》2012,7(10):2305-2312
A divergent method for the synthesis of α,α′‐diarylacenaphtho[1,2‐c]phosphole P‐oxides has been established; α,α′‐dibromoacenaphtho[c]phosphole P‐oxide, which was prepared through a TiII‐mediated cyclization of 1,8‐bis(trimethylsilylethynyl)naphthalene, underwent a Stille coupling with three different kinds of aryltributylstannanes to afford the α,α′‐diarylacenaphtho[c]phosphole P‐oxides in moderate to good yields. X‐ray crystallographic analyses and UV/Vis absorption/fluorescence measurements have revealed that the degree of π‐conjugation, the packing motif, the electron‐accepting ability, and the thermal stability of the acenaphtho[c]phosphole π‐systems are finely tunable with the α‐aryl substituents. All the P?O and P?S derivatives exhibited high stability in their electrochemically reduced state. To use this class of arene‐fused phosphole π‐systems as n‐type semiconducting materials, we evaluated device performances of the bulk heterojunction organic photovoltaics (OPV) that consist of poly(3‐hexylthiophene), an indene‐C70 bisadduct, and a cathode buffer layer. The insertion of the diarylacenaphtho[c]phosphole P‐oxides as the buffer layer was found to improve the power conversion efficiency of the polymer‐based OPV devices. 相似文献
135.
We have demonstrated the presence of magneto-chiral dichroism (MChD) of chiral J-aggregates of zinc chlorins. To the best of our knowledge, this is the first observation of MChD in artificial light-harvesting antennas. 相似文献
136.
Teramura K Iguchi S Mizuno Y Shishido T Tanaka T 《Angewandte Chemie (International ed. in English)》2012,51(32):8008-8011
Have a bit of bubbly: Significant amounts of CO and O(2) gas are evolved in the photocatalytic conversion of CO(2) over layered double hydroxides (LDHs) in water. A simple mixture of the same metal hydroxides, which has the same constituent elements of the LDH, shows low activity for CO and O(2) evolution. Dissolved CO(2) gas was shown to be the source of carbon in the reaction over LDHs in water. 相似文献
137.
We report the systematic elaboration of a cost-effective, interference-minimized assay for the label-free optical transduction of chemical reactions. Recently, we have found that certain complexes formed by arginine-rich cell-penetrating peptides (CPPs) and amphiphilic counteranions can act as synergistic anion carriers in lipid bilayer membranes. Application of this discovery to rapid and reversible cytosolic CPP delivery has been described (Futaki, S.; et al. ACS Chem. Biol. 2006, 1, 299). Here, we report the complementary use of polyarginine (pR)-counteranion complexes as general optical transducers of chemical reactions. Counterion screening revealed dodecyl phosphate (DP) as an ideal pR activator. Carboxyfluorescein (CF)-loaded vesicles with a shelf life of 3.5 years served best for the detection of fluorogenic CF release by pR-DP complexes with the naked eye. Inactivation of pR-DP complexes by counterion exchange with hyaluronan (HA) caused no CF emission, while HA removal by hyaluronidase (HAase) did. pR-DP complexes were further compatible with the optical detection of HA immobilization on solid support as well as inhibitor screening for HAase (cromolyn, heparin) with and without substrate immobilization. Controls concerning binary ATP/ADP discrimination for naked-eye kinase detection are mentioned to delineate scope but also limitations of this simple and quite universal method. 相似文献
138.
139.
140.
Yasuyoshi Miki Makoto Kuromatsu Hideaki Miyatake Hiromi Hamamoto 《Tetrahedron letters》2007,48(52):9093-9095
1-Benzenesulfonylindole-2,3-dicarboxylic anhydride was reacted with aniline to give the 2-carbamoylindole-3-carboxylic acid as the sole product, but with N-methylaniline, the 3-carbamoylindole-2-carboxylic acid was the major product, which could be transformed into the 1-benzenesulfonylbenzo-γ-carbolinone in the presence of Pd(OCOCF3)2. The reduction of the benzo-γ-carbolinone with LiAlH4 gave the cryptosanginolentine in high yield. 相似文献