全文获取类型
收费全文 | 103篇 |
免费 | 1篇 |
专业分类
电工技术 | 9篇 |
化学工业 | 27篇 |
机械仪表 | 17篇 |
建筑科学 | 2篇 |
能源动力 | 7篇 |
轻工业 | 16篇 |
无线电 | 2篇 |
一般工业技术 | 17篇 |
冶金工业 | 5篇 |
自动化技术 | 2篇 |
出版年
2022年 | 1篇 |
2021年 | 2篇 |
2020年 | 1篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 1篇 |
2015年 | 2篇 |
2014年 | 3篇 |
2013年 | 2篇 |
2012年 | 3篇 |
2011年 | 5篇 |
2010年 | 4篇 |
2009年 | 5篇 |
2008年 | 2篇 |
2007年 | 4篇 |
2006年 | 5篇 |
2005年 | 4篇 |
2004年 | 2篇 |
2003年 | 3篇 |
2002年 | 1篇 |
2001年 | 4篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 4篇 |
1991年 | 5篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1975年 | 4篇 |
1974年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有104条查询结果,搜索用时 734 毫秒
1.
The restoration of the red colour of carthamine (photo-bleached in polymeric heterosaccharide gels) was investigated using sodium salts, potassium salts, and alkali. Ca-alginate gel was stained with carthamine, and the red-dish membranes were exposed to fluorescent light for 2·5, 4·0 and 20 h (at 28°C). The resulting orange-yellow gel membranes were treated with Na- or K-citrate solution and the restoration of the red colouration was followed spectrophoto-metrically. The results indicate that the red colour of carthamine can be retained within the gel membranes, while yellow-coloured compounds were removed and/or transformed by the alkaline salt solutions. 相似文献
2.
Wakabayashi K Matsumura T Nakayama Y Koshi M 《The Review of scientific instruments》2011,82(2):026112
We performed miniature flyer impact experiments to investigate the relationship between the apparent (u(a)) and actual (u(A)) particle velocities measured by a velocity interferometer in single-crystal lithium fluoride (LiF) that was shock-compressed along the [100] axis. The miniature flyer was accelerated to velocities in the range 652.5-1937.6 m/s by a tabletop pulsed laser. An empirical relationship of u(a) = (1.2749 ± 0.0102)u(A) was obtained. The obtained relationship agreed well with the results of a previous study within the experimental errors and its uncertainty was less than ±1%. This result indicates that the present experimental technique is effective for measuring the relationship between u(a) and u(A) of shocked transparent materials with a comparable accuracy to conventional methods. 相似文献
3.
Quinjiao Wang Kenji Itaka Hideki Minami Hitoshi Kawaji Hideomi Koinuma 《Science and Technology of Advanced Materials》2004,5(5-6):543
La1−xCaxVO3 composition-spread film library was fabricated by combinatorial pulsed laser deposition and their thermoelectric properties were evaluated paralelly by the multi-channel probes of Seebeck coefficient and electric conductivity. Concurrent X-ray analysis verified the formation of solid soluted films in the full composition range (0x1) as judged from the linear variation of the lattice constants. The Seebeck coefficients of La1−xCaxVO3 changed from a large negative value to almost zero with the increase of x, due presumably to the variation of valence in vanadium ions.The power factor in this library was as high as 0.6 μW/cm K2, which was obtained at x=0, i.e. pure LaVO3 grown at 800 °C. 相似文献
4.
Koshi Takenaka Masayoshi Ichigo Taisuke Hamada Atsushi Ozawa Takashi Shibayama Tetsuya Inagaki 《Science and Technology of Advanced Materials》2014,15(1)
Magnetostructural correlations in antiperovskite manganese nitrides were investigated systematically for stoichiometric and solid solution Mn3Cu1?xAxN (A = Co, Ni, Zn, Ga, Ge, Rh, Pd, Ag, In, Sn or Sb). This class of nitrides is attracting great attention because of their giant negative thermal expansion, which is achieved by doping Ge or Sn into the A site as a relaxant of the sharp volume contraction on heating (spontaneous volume magnetostriction ωs) because of the magnetovolume effects. The physical background of large ωs and mechanism of how the volume contraction becomes gradual with temperature are central concerns for the physics and applications of these nitrides. An entire dataset of thermal expansion, crystal structure and magnetization demonstrates that the cubic triangular antiferromagnetic state is crucial for large ωs. The intimate relationship between ωs and the magnetic structure is discussed in terms of geometrical frustration related to the Mn6N octahedron and magnetic stress concept. The results presented herein also show that ωs depends on the number of d electrons in the A atom, suggesting the important role of the d orbitals of the A atom. Not all the dopants in the A site, but the elements that disturb the cubic triangular antiferromagnetic state, are effective in broadening the volume change. This fact suggests that instability neighboring the phase boundary is related to the broadening. The relation between the gradual volume change and the local structure anomaly is suggested by recent microprobe studies. 相似文献
5.
Effect of running‐in process on friction behaviour of carbon nitride (CNx) coating in N2 gas stream was investigated with a newly introduced two‐step ball‐on‐disk friction test, where the rubbed Si3N4 ball in the pre‐sliding (step 1) was replaced by a new CNx‐coated Si3N4 ball in the subsequent sliding stage under N2 gas (step 2). The two‐step friction test is clarified to be a simple but effective technique for obtaining contact material combination of self‐mated CNx coatings and for achieving stable and low frictions of CNx coatings. Friction coefficients of CNx/CNx in N2 gas stream decrease greatly from 0.07 without pre‐sliding to less than 0.025 in two‐step friction tests. The minimum friction coefficient of 0.004 was obtained by introducing 500 cycles of pre‐sliding in ambient air. These stable and low frictions are attributed to the generation of self‐mated CNx coatings and the formation of a lubricious layer on the disk surface. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
6.
Koshi Takenaka Miku Sato Masaya Mitamura Yasunori Yokoyama Naoyuki Katayama Yoshihiko Okamoto 《Journal of the American Ceramic Society》2020,103(4):2757-2763
We used spray-dry method to synthesize fine powder of β-Cu1.8Zn0.2V2O7 showing large negative thermal expansion (NTE) linearly to temperature over a wide temperature range. The NTE of β-Cu1.8Zn0.2V2O7 is produced by microstructures consisting of voids and anisotropic thermal deformation of crystal grains in ceramics. By reducing the size of the microstructures that produce NTE, large NTE equivalent to that of bulk was realized, even for ceramic particles of about 2 μm size. Comparison with particles produced using a conventional method demonstrates that the particle size distribution is narrow and that the particles are nearly spherical. This achievement is expected to pave the way to use of NTE materials in micrometer-scale control of thermal expansion. 相似文献
7.
Water lubrication using diamond-like carbon (DLC) coatings is regarded as being a promising eco-friendly technology. However, it has been reported that delamination of DLC coatings occurs in water. The authors clarified that the application of friction in ambient air prior to self-mating DLC water lubrication, in addition to the suppression of DLC delamination, caused the friction coefficient to decrease more than when no processing is performed in the boundary lubrication region. When compared to the case when there was no pre-sliding, in terms of the wear scar, in this case, a much more hydrophilic and smoother surface was formed. Therefore, the friction-reducing process in water due to the presence of a sliding history (pre-sliding in ambient air) was clarified by an analysis of the DLC geometry, structure, chemical state and an in situ analysis that can measure the friction properties and the chemical state of DLC. We clarified that the process in which the oxidation and structural changes of the DLC proceed at the time of pre-sliding in ambient air using in situ Fourier transform infrared spectroscopy–attenuated total reflection. It was also revealed that the OH termination subsequently accelerated rapidly due to the friction in water after pre-sliding process. In addition, a time-of-flight secondary ion mass spectrometry analysis revealed that this OH group was derived from the lubricating water and unlike the case in which there was no pre-sliding in ambient air, the rate at which OH terminates increased considerably. 相似文献
8.
The copolymerization of glycidylmethacrylate–methylmethacrylate–divinylbenzene in cyclohexane was studied as an example of crosslinking precipitation copolymerization. The resultant copolymer is fine spheroidal. The copolymerization proceeds acceleratively at first, then steadily, and gradually slows down. The larger the divinylbenzene concentration, the smaller is the copolymerization rate. Glycidylmethacrylate is preferentially incorporated in the copolymer. 相似文献
9.
Takanori Takeno Shingo Abe Koshi Adachi Hiroyuki Miki Toshiyuki Takagi 《Diamond and Related Materials》2010,19(5-6):548-552
In this study we developed composite coatings consisting of amorphous hydrogenated carbon (a-C:H) and molybdenum-disulfide (MoS2), and clarified their microstructure. In addition, we interpreted the tribological properties of the composite coatings in the viewpoint of a deposition-induced microstructural modification. The coatings were produced by the hybrid deposition technique of RF-generated methane and argon plasma and DC magnetron co-sputtering of MoS2 target. The deposition parameter investigated in this study was methane flow rate. Structural analyses were performed using a transmission electron microscope (TEM) and an atomic force microscope (AFM). Friction tests were conducted using a ball-on-disk type tribometer. From an electron micrograph, it was confirmed that nano-clusters were embedded into an amorphous carbon host matrix. Surface roughness of the composite coating was ~ 0.25 nm in Ra compared to 5.0 nm in Ra of sputtered MoS2. The concentration measurements were performed, and the results show that the sulfur and molybdenum concentration ratio, [S]/[Mo], is ~ 0.9, which indicates that the amount of sulfur was reduced due to the discharged plasma. In friction tests, composite coatings showed high friction in a vacuum condition. It was considered that lubricant MoS2 lamellar structures showing super-low friction in a vacuum condition during friction could not be formed between ball and coating during friction because of the lack of sulfur in embedded clusters. 相似文献
10.
Zahrul Fuadi Koshi Adachi Hideaki Ikeda Hisataka Naito Koji Kato 《Tribology Letters》2009,33(3):169-178
In this paper, a fundamental mechanism for creep-groan generation is investigated by adopting a simple yet effective caliper-slider
experimental model. Contact condition, which is a function of three parameters, namely normal force, contact roughness, and
material combination, is connected with the creep-groan phenomenon in terms of contact stiffness. Creep-groan generation is
determined by analyzing the frequency characteristic of the generated vibration acceleration when the sliding commences due
to a simultaneous application and release of force in the tangential and normal directions, respectively. As per the obtained
results, creep-groan occurrence or absence in the employed experimental model may be classified into three regions based upon
the value of the contact stiffness, i.e., occurrence, non-occurrence, and mixed regions. The results also indicate that creep-groan
occurrence in this caliper-slider experimental model can be avoided by controlling the value of contact stiffness in an effective
manner. 相似文献