全文获取类型
收费全文 | 152篇 |
免费 | 8篇 |
专业分类
化学 | 122篇 |
晶体学 | 1篇 |
力学 | 3篇 |
数学 | 7篇 |
物理学 | 27篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 3篇 |
2019年 | 5篇 |
2018年 | 1篇 |
2017年 | 5篇 |
2016年 | 6篇 |
2015年 | 4篇 |
2014年 | 2篇 |
2013年 | 10篇 |
2012年 | 9篇 |
2011年 | 10篇 |
2010年 | 3篇 |
2009年 | 7篇 |
2008年 | 10篇 |
2007年 | 10篇 |
2006年 | 8篇 |
2005年 | 8篇 |
2004年 | 14篇 |
2003年 | 4篇 |
2002年 | 7篇 |
2001年 | 5篇 |
2000年 | 5篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1995年 | 5篇 |
1994年 | 1篇 |
1992年 | 2篇 |
1986年 | 2篇 |
1984年 | 2篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1975年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有160条查询结果,搜索用时 31 毫秒
91.
Gas chromatography–laser ionization time-of-flight mass spectrometry (GC-LI-TOFMS) was applied to the analysis of fuel oil in soil and soil treated by bioremediation. To demonstrate rapid and selective measurement, only filtered samples after extraction of fuel oil from soil were prepared. The required time for preparing three sample solutions from an oil-contaminated soil sample was only ca. 30?min. The degree of the decrease in the fuel oil in a soil sample by vaporization was confirmed by GC-LI-TOFMS, and after 7 days, the five peak areas arising from the constituents in fuel oil were decreased to between 39 and 79% of their original values. Next, the effect of bioremediation was confirmed by the addition of microbes (Rhodococcus sp. and Acinetobacter sp.). As a result, after 7 days, the five peak areas were decreased to between 61 and 81% of the values of the first decreases, after allowing for the effect of vaporization. This method showed sufficient selectivity, robustness, and rapidity for the measurement of oil-contaminated soil treated by bioremediation, which is essential for the evaluation of real environmental remediation. 相似文献
92.
We compute the bulk entanglement entropy of a massive scalar field in a Poincare AdS with the Dirichlet and Neumann boundary condition when we trace out a half space. Moreover, by taking into account the quantum back reaction to the minimal surface area, we calculate how much the entanglement entropy changes under a double‐trace deformation of a holographic CFT. In the AdS3/CFT2 setup, our result agrees with the known result in 2d CFTs. In higher dimensions, our results offer holographic predictions. 相似文献
93.
Poly(l-lactic acid)-TiO2 nanoparticle nanocomposite films were prepared by incorporating surface modified TiO2 nanoparticles into polymer matrices. In the process of preparing the nanocomposite films, severe aggregation of TiO2 nanoparticles could be reduced by surface modification by using carboxylic acid and long-chain alkyl amine. As a result, the nanocomposite films with high transparency, similar to pure PLA films, were obtained without depending on the amount of added TiO2 nanoparticles. A TEM micrograph of the nanocomposite films suggests that the TiO2 nanoparticles of 3-6 nm in diameter were uniformly dispersed in polymer matrices. Photodegradation of PLA-TiO2 nanoparticle nanocomposite films was also investigated. The results showed that nanocomposite films could be efficiently photodegraded by UV irradiation in comparison with pure PLA. 相似文献
94.
Miyagawa T Yamamoto M Muraki R Onouchi H Yashima E 《Journal of the American Chemical Society》2007,129(12):3676-3682
A water-soluble amphiphilic poly(phenylacetylene) bearing the bulky aza-18-crown-6-ether pendants forms a one-handed helix induced by l- or d-amino acids and chiral amino alcohols through specific host-guest interactions in water. We now report that such an induced helical poly(phenylacetylene) with a controlled helix sense can selectively trap an achiral benzoxazole cyanine dye among various structurally similar cyanine dyes within its hydrophobic helical cavity inside the polymer in acidic water, resulting in the formation of supramolecular helical aggregates, which exhibit an induced circular dichroism (ICD) in the cyanine dye chromophore region. The supramolecular chirality induced in the cyanine aggregates could be further memorized when the template helical polymer lost its optical activity and further inverted into the opposite helicity. Thereafter, thermal racemization of the helical aggregates slowly took place. 相似文献
95.
Takanori Takahashi Kazuhiro Ikegaya Hirohmi Watanabe Nobukazu Miyagawa Shigeru Takahara Tsuguo Yamaoka 《先进技术聚合物》2000,11(6):307-315
A novel water‐dispersible reactive microgel, which had a diameter of 40–90 nm, was synthesized for photopolymer materials. The microgels have segments with substituted ammonium groups, to provide water solubility, in their polymer networked structure. It has unsaturated groups connected to the quaternary nitrogens by ionic bonding (I‐type microgel). The I‐type microgel was compared with one that has methacryloyl groups connected with the quaternary nitrogens of the microgel by covalent bonding (C‐type microgel). The I‐type microgels were able to separately control the modified amount of quaternary nitrogen and methacryloyl group. In the presence of 2,4‐diethylthioxantone as a photoinitiator and pentaerthritol triacrylate as a crosslinker, the photopolymer containing the C‐type or I‐type microgels had sensitivity high enough for practical use. Not only the amount of the methacryloyl group of the microgel but the amount of the quaternary nitrogen affected the sensitivity and the rate of polymerization of the water‐dispersible photopolymer containing the I‐type microgels. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
96.
Masashi Miyagawa 《Annals of Operations Research》2012,196(1):443-458
This paper derives analytical expressions for the rectilinear distance to a facility in the presence of a square barrier. The distribution of the barrier distance is derived for two regular patterns of facilities: square and diamond lattices. This distribution, which provides all the information about the barrier distance, will be useful for facility location problems with barriers and reliability analysis of facility location. The distribution of the barrier distance demonstrates how the location and the size of the barrier affect the barrier distance. A?numerical example shows that the total barrier distance increases as the barrier gets closer to a facility, whereas the maximum barrier distance increases as the barrier becomes greater in size. 相似文献
97.
Calculations of K¯ d → π Σn in the Λ(1405) resonance region are presented taking into account single scattering and two-step processes. The influence of some common approximations in the kinematics on the predicted lineshape for the resonance are discussed. 相似文献
98.
Viscoelastic properties of poly(methyl methacrylate) with high glass transition temperature by lithium salt addition
下载免费PDF全文
![点击此处可从《Journal of Polymer Science.Polymer Physics》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Azusa Miyagawa Viknasvarri Ayerdurai Shogo Nobukawa Masayuki Yamaguchi 《Journal of Polymer Science.Polymer Physics》2016,54(22):2388-2394
The effect of ion‐dipole interaction between lithium cations and oxygen atoms in poly(methyl methacrylate) (PMMA), which leads to the great enhancement of glass transition temperature (Tg), on the linear viscoelastic properties is studied using binary blends of PMMA and lithium trifluoromethanesulfonate (LiCF3SO3). The strong interaction at low temperature leads to the high modulus in the glassy region even near Tg. The interaction becomes weak as increasing the temperature. Consequently, the rheological terminal region is clearly detected without a marked enhancement of steady‐state compliance, although the zero‐shear viscosity increases by the LiCF3SO3 addition. The result indicates that the crosslinking due to the ion‐dipole interaction has a lifetime that decides the longest relaxation time. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2388–2394 相似文献
99.
Masashi Miyagawa 《TOP》2017,25(1):95-110
This paper develops a bi-objective model for determining the location, size, and shape of a finite-size facility. The objectives are to minimize both the closest and barrier distances. The closest distance represents the accessibility of customers, whereas the barrier distance represents the interference to travelers. The distributions of the closest and barrier distances are derived for a rectangular facility in a rectangular city where the distance is measured as the rectilinear distance. The analytical expressions for the distributions demonstrate how the location, size, and shape of the facility affect the closest and barrier distances. A numerical example shows that there exists a trade-off between the closest and barrier distances. 相似文献
100.