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101.
气相爆轰波平衡胞格稳定性实验研究 总被引:2,自引:1,他引:2
本文详细介绍了研究气体爆轰的烟迹法以及采用所提出的方法得到的爆轰波通过柔性材料壁面前后平衡胞格形成、消失和重新恢复的全过程烟迹照片。实验按初压不同分五组进行。从烟迹照片中各时期的胞格尺寸、横波的变化出发,对上述过程中横波强度变化情况及柔性壁面对横波的作用和影响进行了分析,对平衡胞格恢复的条件进行了讨论。 相似文献
102.
作者分别用圆形和方形爆轰管,通过改变惰性气体的比例和圆锥管道的锥角,对H2-O2和C2H2-O2系统进行了爆轰临界直径的实验研究,得到了不同稀释浓度下方管中爆轰波熄灭的临界直径,验证了Mitrofanov.V.V.和Soloukhin,R.I.以前得到的结果(dc/=10),也得到了圆锥管道中不同锥角对临界直径的影响(dc/-),并用流管理论对实验结果作了初步的分析。 相似文献
103.
M. A. El-sayed 《Journal of Chemical Sciences》1991,103(3):277-282
The determination of the mechanisms of chemical and physical changes is one of the principal occupations of many chemists
today. To accomplish this, the dependence of the change being examined on a number of intensive variables such as temperature,
pressure, concentration of reactants as well as the pH is usually studied. In this account, we summarize our recent studies
on the reactivity and dynamics of niobium gaseous clusters in which their changes with size are used as a new degree of freedom
that assists in deducing the mechanism of the change studied. 相似文献
104.
《科学通报(英文版)》2004,49(Z1):79-79
The mechanism of carbon isotopic fractionation for gaseous hydrocarbons is revealed by investigating the residual liquid hydrocarbons in laboratory pyrolysates of n-octodecane. The results indicate that cracking and polymerization in the relatively low temperatures and dispropor-tionation reactions leading to light hydrocarbons and pol-yaromatic hydrocarbons at high temperatures are probably causes for the carbon isotope reversal of gaseous hydrocarbons that is commonly observed in pyrolysis experiments. This study provides significant insight for quantitative modeling of natural gas δ13C values and aid in the identification and assessment of natural gases derived from oil cracking. 相似文献
105.
Kohji Mitsubayashi Genki Nishio Masayuki Sawai Elito Kazawa Hiromichi Yoshida Takao Saito Hiroyuki Kudo Kimio Otsuka Motoharu Takao Hirokazu Saito 《Mikrochimica acta》2008,160(4):427-433
A biochemical gas-sensor (sniffer-chip) with formaldehyde dehydrogenase (FALDH) was developed for convenient analysis of gaseous
formaldehyde with high gas-selectivity. The sniffer-chip for formaldehyde in the gas phase was constructed by immobilizing
FALDH to a Pt-electrode coated hydrophilic PTFE membrane. The oxidation current of NADH produced by the enzymatic reactions
was measured by amperometric analysis. The calibration range of the sniffer-chip for formaldehyde in the gas phase was from
40 to 2000 ppb, which encountered the maximum permissible concentration of formaldehyde vapor in the residential house (80 ppb)
and formaldehyde detection limit for the human sense of smell (410 ppb). As the resident-environmental application, the sniffer-chip
was possible to measure the formaldehyde concentration from some timber materials (3 kinds of interior timber and 2 kinds
of exterior formwork timber) within 3 min. The calculated concentration value by a regression analysis was consistent with
those of a commercially available gas sensor and a gas detector tube for formaldehyde. The FALDH sniffer-tip would be effective
and convenient approach to detect and measure gaseous formaldehyde with high gas-selectivity at the residential atmosphere.
Correspondence: Kohji Mitsubayashi, Department of Biomedical Devices and Instrumentation, Institute of Biomaterials and Bioengineering,
Tokyo Medical and Dental University, 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan 相似文献
106.
针对电子教学系统人机交互的自然性和用户适应性不足的问题,研究设计了基于草图的人机交互技术的新型电子教学系统,提出了基于用户信息的草图识别方法.实验表明该方法具有很好的效果. 相似文献
107.
108.
Freneil B. Jariwala Ryan E. Wood Upul Nishshanka Athula B. Attygalle 《Journal of mass spectrometry : JMS》2012,47(4):529-538
In the negative‐ion collision‐induced dissociation mass spectra of most organic sulfonates, the base peak is observed at m/z 80 for the sulfur trioxide radical anion (SO3–·). In contrast, the product‐ion spectra of a few sulfonates, such as cysteic acid, aminomethanesulfonate, and 2‐phenylethanesulfonate, show the base peak at m/z 81 for the bisulfite anion (HSO3–). An investigation with an extensive variety of sulfonates revealed that the presence of a hydrogen atom at the β‐position relative to the sulfur atom is a prerequisite for the formation of the bisulfite anion. The formation of HSO3– is highly favored when the atom at the β‐position is nitrogen, or the leaving neutral species is a highly conjugated molecule such as styrene or acrylic acid. Deuterium‐exchange experiments with aminomethanesulfonate demonstrated that the hydrogen for HSO3– formation is transferred from the β‐position. The presence of a peak at m/z 80 in the spectrum of 2‐sulfoacetic acid, in contrast to a peak at m/z 81 in that of 3‐sulfopropanoic acid, corroborated the proposed hydrogen transfer mechanism. For diacidic compounds, such as 4‐sulfobutanoic acid and cysteic acid, the m/z 81 ion can be formed by an alternative mechanism, in which the negative charge of the carboxylate moiety attacks the α‐carbon relative to the sulfur atom. Experiments conducted with deuterium‐exchanged and deuterium‐labeled analogs of sulfocarboxylic acids demonstrated that the formation of the bisulfite anion resulted either from a hydrogen transfer from the β‐carbon, or from a direct attack by the carboxylate moiety on the α‐carbon. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
109.
The Monchick–Mason approximation for the calculation of the transport coefficients of atomic ions in diatomic gases is extended in a manner that allows comparison of theoretical and experimental mobilities of gaseous ions to serve as quantitative tests of the accuracy of the ab initio, angle- and position-dependent interaction potentials used in the calculations. The feasibility of this procedure is demonstrated with Li+ in H2. 相似文献
110.