全文获取类型
收费全文 | 165篇 |
免费 | 2篇 |
专业分类
化学 | 161篇 |
数学 | 1篇 |
物理学 | 5篇 |
出版年
2021年 | 3篇 |
2020年 | 1篇 |
2018年 | 2篇 |
2016年 | 3篇 |
2015年 | 1篇 |
2014年 | 1篇 |
2013年 | 14篇 |
2012年 | 3篇 |
2011年 | 6篇 |
2010年 | 3篇 |
2009年 | 2篇 |
2008年 | 11篇 |
2007年 | 11篇 |
2006年 | 10篇 |
2005年 | 4篇 |
2004年 | 11篇 |
2003年 | 10篇 |
2002年 | 3篇 |
2001年 | 9篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1998年 | 4篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 5篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 3篇 |
1989年 | 2篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 5篇 |
1983年 | 1篇 |
1982年 | 6篇 |
1981年 | 6篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 1篇 |
排序方式: 共有167条查询结果,搜索用时 46 毫秒
1.
Kenichi Oyaizu Junya Katoh Fumiaki Suzuki Mitsutoshi Jikei Kimihisa Yamamoto Hiroyuki Nishide Eishun Tsuchida 《先进技术聚合物》1991,2(3):155-159
Oligo(phenylene sulfide) (OPS) containing one disulfide bond at the end of the chain, which was obtained by the oxidative polymerization of diphenyl disulfide, had a relatively low Td10%(temperature for 10% weight loss) of 412 °C because of degradation of the disulfide bond. But this thermal cleavage of the disulfide bond promoted the curing reaction through thiophenoxy radical formation. OPS was allowed to react with diiodobenzene at 220 °C. The thermal stability of OPS was improved through the consumption of the disulfide bond and the coupling of the chain. 相似文献
2.
Stability of porphyrin-calix[4]arene complexes analyzed by electrospray ionization mass spectrometry
Arai S Ishihara S Takeoka S Ohkawa H Shibue T Nishide H 《Rapid communications in mass spectrometry : RCM》2004,18(18):2065-2068
The stability of some porphyrin-calix[4]arene sodium-ion complexes were determined by a collision-activated decomposition (CAD) method utilizing electrospray ionization mass spectrometry (ESI-MS). Comparing the values of E(1/2), the collision energy at which the relative intensity of the complex ion is 0.5, we found that the porphyrin-calix[4]arene complex with the higher value of E(1/2) corresponded to that with the larger association constant (Kass), as measured by 1H-NMR in CDCl3. Both our ESI-MS and NMR studies proved that the number of hydrogen bonds and the rigidity of the calix[4]arene stabilized the complex. The ESI-MS technique could be successful in screening the binding affinity in host-guest systems with a small amount of sample. 相似文献
3.
Manabu Tanaka Kaoru Hatta Tomohiko Edura Ken Tsutsui Yasuo Wada Hiroyuki Nishide 《先进技术聚合物》2007,18(11):925-931
The electric conductivity of π‐conjugated and radical‐bearing polymers, i.e., polythiophenes bearing pendant galvinoxyl and phenoxyl radical groups, was measured using a microcomb‐shaped electrode. The electric conductivity was found to be enhanced by the radical content in the polymer. The infrared (IR) and Raman spectroscopies suggested a structural change from an aromatic form to a quinoid one in the polythiophene backbone by the phenoxyl radical generation. The effect of the pendant galvinoxyl radical's unpaired electron on the electric conductivity of the polythiophene was discussed by comparing the conductivity of a radical‐bearing polystyrene and a polythiophene mixed with low‐molecular radical molecules. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
4.
Kiyoharu Nishide Shin-ichi Ohsugi Tetsuo Miyamoto Kamal Kumar Manabu Node 《Monatshefte für Chemie / Chemical Monthly》2004,135(2):189-200
Summary. Development of new odorless thiols (dodecanethiol, 4-n-heptylphenylmethanethiol, 4-trimethylsilylphenylmethanethiol, 4-trimethylsilylbenzenethiol) and an odorless sulfide (1-methylsulfanyldodecane) and their applications to dealkylation, Michael addition, Swern oxidation, and Corey-Kim oxidation are described. 相似文献
5.
Kenji Miyatake Mitsutoshi Jikei Junya Katoh Kimihisa Yamamoto Hiroyuki Nishide Eishun Tsuchida 《先进技术聚合物》1994,5(4):216-220
Poly(2,5-dimethylphenylene sulfide) was prepared by oxidative polymerization of sulfur chloride with p-xylene using 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) as an oxidizing agent. The reaction proceeded efficiently under atmospheric pressure and at room temperature. The polymer formed had a high melting temperature and linear structure which was confirmed by spectroscopies. The effects of reaction time, solvent, temperature and oxidizing agent on polymerization are also discussed. 相似文献
6.
Shin-ichi OhsugiKiyoharu Nishide Keiji OonoKazunori Okuyama Masato FudesakaSumiaki Kodama Manabu Node 《Tetrahedron》2003,59(42):8393-8398
Development of the odorless dodecyl methyl sulfide (Dod-S-Me, 1) as an alternative for dimethyl sulfide (DMS) and new odorless methods for the Corey-Kim and Swern oxidations are described. These reactions have been developed with a view toward green chemistry, utilizing Dod-S-Me (1) and common solvents instead of dichloromethane. 相似文献
7.
Komatsu T Hayakawa S Tsuchida E Nishide H 《Chemical communications (Cambridge, England)》2003,(1):50-51
alpha-Cyclodextrin (alpha CD)-penetrating 2-methyl-1-phenethylimidazole coordinates to the zinc(II) and iron(II) complexes of meso-tetrakis[o-(N-methyl)pyridinium] porphyrinate, giving non-covalently linked alpha CD-porphyrin ensembles; the iron(II) complex can reversibly bind and release dioxygen in aqueous DMF solution. 相似文献
8.
[reaction: see text] The Michael addition to alpha-substituted alpha,beta-unsaturated esters and amides using complex A containing a chiral odorless thiol proceeded diastereoselectively. The Michael adducts were converted to beta-mercapto esters and amides via a Wagner-Meerwein rearrangement with boron trifluoride etherate and a thiol exchange reaction using odorless 1-dodecanethiol. This conversion constitutes a formal asymmetric Michael addition of hydrogen sulfide to alpha,beta-unsaturated carbonyl compounds using odorless thiols instead of the toxic hydrogen sulfide. 相似文献
9.
Star-shaped poly(1,2-phenylenevinylene)s 4-substituted with multiple pendant phenoxyls (2 and 3) were synthesized by polymerizing 2-bromo-4-(acetoxyphenyl)styrene in the presence of 1,3,5-triiodobenzene or 1,3,5-tris(3',5'-diiodophenyl)benzene as the core via a simple one-pot Heck reaction and subsequent hydrolysis, phenolate formation, and heterogeneous oxidation. ESR spectra indicated a delocalized spin distribution into the core parts of the star-shaped molecules. The polyradicals, 2 and 3, were in a high-spin state at low temperature, and the ferromagnetic behavior was enhanced for the polyradical with a higher molecular weight. Although an average S of 3 remained at 3/2 to 4/2, the polyradical 2 even with a spin concentration of 0.8 spin/unit revealed an average S of 7/2 to 8/2. The 1,3,5-benzene core acted as an effective magnetic coupler to align the spins of the pendant phenoxyls through the star-shaped pi-conjugated backbone. 相似文献
10.
Sol-gel-derived titania films were analyzed by temperature programmed desorption (TPD) and X-ray diffraction (XRD) techniques.
The relationship between the TPD curves measured for two types of titania gel films and their crystal structures was investigated.
On the basis of the analyses, a preparation process for a titania sol solution containing anatase nanocrystals was designed
and developed. Using this process, a colloidal anatase titania sol solution was prepared by heating aqueous titanium hydroxide
containing HCl at 60°C for 2 h. The nanocrystal structure of the titania films obtained by coating the sol on glass substrates
was confirmed by TPD and XRD measurements. 相似文献