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排序方式: 共有136条查询结果,搜索用时 31 毫秒
31.
Akihiko Okumura Yasuaki Takada Susumu Watanabe Hiroaki Hashimoto Naoya Ezawa Yasuo Seto Yasuo Takayama Ryoji Sekioka Shintaro Yamaguchi Shintaro Kishi Takafumi Satoh Tomohide Kondo Hisayuki Nagashima Tomoki Nagoya 《Journal of the American Society for Mass Spectrometry》2016,27(7):1219-1226
We propose detecting a fragment ion (Ph2As+) using counter-flow introduction atmospheric pressure chemical ionization ion trap mass spectrometry for sensitive air monitoring of chemical warfare vomiting agents diphenylchloroarsine (DA) and diphenylcyanoarsine (DC). The liquid sample containing of DA, DC, and bis(diphenylarsine)oxide (BDPAO) was heated in a dry air line, and the generated vapor was mixed into the humidified air flowing through the sampling line of a mass spectrometer. Humidity effect on the air monitoring was investigated by varying the humidity of the analyzed air sample. Evidence of the in-line conversion of DA and DC to diphenylarsine hydroxide (DPAH) and then BDPAO was obtained by comparing the chronograms of various ions from the beginning of heating. Multiple-stage mass spectrometry revealed that the protonated molecule (MH+) of DA, DC, DPAH, and BDPAO could produce Ph2As+ through their in-source fragmentation. Among the signals of the ions that were investigated, the Ph2As+ signal was the most intense and increased to reach a plateau with the increased air humidity, whereas the MH+ signal of DA decreased. It was suggested that DA and DC were converted in-line into BDPAO, which was a major source of Ph2As+. 相似文献
32.
Watanabe Hayato Omura Takuya Okaichi Naoto Kano Masanori Sasaki Hisayuki Arai Jun 《Optical Review》2022,29(4):366-374
Optical Review - Light field displays can display three-dimensional (3D) images with smooth motion parallax without the use of special glasses, by reproducing light ray information from objects.... 相似文献
33.
The photo-sensitive self-motion of a benzoquinone (BQ) disk was investigated on a hydroquinone (HQ) aqueous solution. The mode-switching of self-motion, i.e., continuous → intermittent → no motion, was observed with an increase in the concentration of HQ. Upon irradiation with UV light (~254 nm), the critical concentrations of HQ that were associated with the three modes of motion shifted to lower values, and the average speed of motion decreased. We discuss the mechanism of the photo-sensitive self-motion in relation to the photochemical reaction from BQ to HQ and the driving force of the disk. 相似文献
34.
K Nagai M Arito Y Takakuwa S Ooka T Sato MS Kurokawa K Okamoto T Uchida N Suematsu T Kato 《Electrophoresis》2012,33(13):2028-2035
Anti-ribonucleoprotein (anti-RNP) antibodies are one of the representative autoantibodies detectable in patients with systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD). Generally, posttranslational modifications (PTMs) on autoantigens are proposed to be involved in the production of autoantibodies. In this study, we tried to detect the alteration in PTMs on a U1 small nuclear RNP 68k subunit (U1-68k), a major antigen of anti-RNP antibodies. Peripheral blood mononuclear cells (PBMCs) were obtained from patients with MCTD, SLE, and rheumatoid arthritis (RA), and from healthy donors. U1-68ks in the PBMCs were detected by 2D Western blot (WB), where extracted nuclear proteins were separated by 2DE, followed by the detection of U1-68k using WB. More than 20 PTM isoforms were detected with different molecular weights of 65.0 , 66.5, and 68.0kDa, and different pIs between 6.0 and 8.5. Importantly, the relative intensity of the spot with 66.5 kDa and pI 7.5 was significantly increased in the MCTD and SLE groups compared to the RA and healthy groups. Further, this U1-68k isoform, in particular, in its RS domain, was found to have significantly decreased phosphorylation compared to the other isoforms. The PTM alternation may be one of the steps to generate the anti-RNP antibodies. 相似文献
35.
黄花倒水莲皂甙Reinioside C在大鼠体内代谢产物的鉴定 总被引:3,自引:0,他引:3
为了探讨五环三萜皂甙ReiniosideC在大鼠体内代谢产物的结构,单剂量口服ReiniosideC,5h后放血处死,用制备型高效液相色谱方法对血液和各脏器进行提取分离,从大肠内容物和粪中,分离得到了7种代谢产物.用FAB-MS,1H NMR和13C NMR方法鉴定了它们的结构. 相似文献
36.
Hisayuki Tsukuma 《Annals of the Institute of Statistical Mathematics》2003,55(3):447-466
The estimation problem in multivariate linear calibration with elliptical errors is considered under a loss function which
can be derived from the Kullback-Leibler distance. First, we discuss the problem under normal errors and give unbiased estimate
of risk of an alternative estimator by means of the Stein and Stein-Haff identities for multivariate normal distribution.
From the unbiased estimate of risk, it is shown that a shrinkage estimator improves on the classical estimator under the loss
function. Furthermore, from the extended Stein and Stein-Haff identities for our elliptically contoured distribution, the
above result under normal errors is extended to the estimation problem under elliptical errors. We show that the shrinkage
estimator obtained under normal models is better than the classical estimator under elliptical errors with the above loss
function and hence we establish the robustness of the above shrinkage estimator. 相似文献
37.
38.
N. Gunasekara T. Takahashi F. Maeda T. Sagawa H. Suematsu 《Zeitschrift für Physik B Condensed Matter》1988,70(3):349-355
The electronic band structure of the first stage alkali-metal graphite intercalation compounds (C8K, C8Rb and C8Cs) was determined by angle-resolved ultraviolet photoelectron spectroscopy. The dispersive feature of the * bands at
point in the Brillouin zone was clearly observed in all the compounds. The electron occupancies in the * band of C8K, C8Rb and C8Cs were estimated to be 0.5±0.05 e (e; unit electronic charge), 0.45±0.05 e and 0.4±0.05 e, respectively. This strongly suggests that another half of the unit electronic charge is accommodated in the three-dimensional band at point, which forms a spherical Fermi surface at the center of the Brillouin zone. The character of the three-dimensional band at point was also discussed.He died on 27th of September, 1986 相似文献
39.
40.
The enumeration theory is extended in this work into a more general theory, taking back-reactions into consideration. The solutions may faithfully reproduce real processes from arbitrary starting points to a steady-state. Therefore, the presented theory includes the equilibrium theory by Jacobson-Stockmayer, the numerical solution by Gordon-Temple, and the irreversible theory by the present authors. The solutions are described first in general forms of transition probabilities {P}, and then explicitly with the aid of rate equations; simple proofs are given. The presented theory was applied to an experimental data: the distribution of cyclic species in poly(ethylene terephthalate). We shall show that agreement between theory and experiment is nearly perfect.AB model
N
0
Total number of units
-
V
System volume
-
C
0=N
0/N
A
·V
Initial concentration (N
A
: Avogadro's number)
-
L
x
AB type chain x-mer; (AB)x
-
N
x
Number of AB type x-mers
-
R
x
Ring x-mer
-
N
Rx
Number of ring x-mers
-
E
Small molecule eliminated by bond-formation
-
N
E
Number of small molecules eliminated by bond-formation
-
h
k
Number of reacted functional units (f.u.) in statek
-
k
Number of reacted functional units (f.u.) in chains in statek
-
k
Total number of units in chains in statek
-
D=h
k
/N
0
Extent of reaction in statek
-
D
*=
k
/
k
Extent of reaction in chains in statek
-
k
L
Chain-propagation rate constant
-
k
Rx
Cyclization rate constant of chain x-mers
-
k
B
Bond breakage rate constant of chains
-
k
B,Rx
Bond breakage rate constant of cyclic x-mers
- <k
Rx
>
k
Mean cyclization rate constant in statek
-
g(x)=k
B,Rx
/k
B
Ring-opening factor of cyclic x-mers
-
P
Lx,k
Probability that a chain x-mer will be formed in statek
- {P}
Set of transition probabilities per single jump in forward direction or reverse direction (see the text on individual transition probabilities)
AB model
M
A
Total AA monomer unit number
-
M
B
Total BB monomer unit number
-
M
0=M
A
+M
B
Total particle number
-
A,i
=2M
A
–h
i
Unreacted A functional unit (f.u.) number in statei
-
B,i
=2M
B
–h
i
Unreacted B f.u. number in statei
-
Ax
Unreacted A f.u. number on x-mers
-
h
i
Number of reacted A (or B) f.u. in statei
-
i
Number of reacted A (or B) f.u. in chains in statei
-
A,i
=2M
A
–h
i
+
i
A f.u. number in chains in statei
-
B,i
=2M
B
–h
i
+
i
B f.u. number in chains in statei
-
i
=2(M
0–h
i
+
i
)
Total f.u. number in chains in statei
-
D=h
i
/M
0
Extent of reaction in statei
-
D
A
*
=
i
/
A,i
Extent of reaction of A f.u. in chains in statei
-
D
B
*
=
i
/
B,i
Extent of reaction of B f.u. in chains in statei
-
D
*=2
i
/
i
Extent of reaction in chains in statei
-
L
x
(AA-BB)x-1-AA type chain x-mer;x=1,2,3,...
-
L
x
BB-(AA-BB)x type chain x-mer;x=0,1,2,...
-
L
x
(AA-BB)x type chain x-mer;x=1,2,3,...
-
N
x
Number of type x-mers
-
N
x
Number of type x-mers
-
N
x
Number of type x-mers 相似文献