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91.
Deutseche Atomgewitchs-Kommision G. P. Baxter Union internationale de chemiepure et appliquée C. G. Addingley R. Whytlaw-Gray H. W. Starkweather L. R. Pire E. Moles A. S. King R. T. Birge M. Ritchie Th. W. Richards A. W. Philips W. D. Harkins B. Mortimer A. Cousen W. E. St. Turner R. K. Mc Alphine S. D. Muzaffar W. Noddack Ida Noddack und J. Shimaru 《Fresenius' Journal of Analytical Chemistry》1930,81(1-2):42-45
Ohne Zusammenfassung 相似文献
92.
Nagayama Y Kawahata K Inagaki S Peterson BJ Sakakibara S Tanaka K Tokuzawa T Watanabe KY Ashikawa N Chikaraishi H Emoto M Funaba H Goto M Hamada Y Ichiguchi K Ida K Idei H Ido T Ikeda K Imagawa S Isayama A Isobe M Iwamoto A Kaneko O Kitagawa S Komori A Kubo S Kumazawa R Masuzaki S Matsuoka K Mito T Miyazawa J Morisaki T Morita S Motojima O Murakami S Mutoh T Muto S Nakajima N Nakamura Y Nakanishi H Narihara K Narushima Y Nishimura A Nishimura K Nishizawa A Noda N Ohdachi S Ohkubo K Ohyabu N 《Physical review letters》2003,90(20):205001
Sawtooth oscillations have been observed in current-carrying helical plasmas by using electron-cyclotron-emission diagnostics in the Large Helical Device. The plasma current, which is driven by neutral beam injection, reduces the beta threshold of the sawtooth oscillation. When the central q value is increased due to the plasma current, the core region crashes, and, when it is decreased, the edge region crashes annularly. Observed rapid mixture of the plasma in the limited region suggests that these sawtooth crashes are reconnection phenomena. Unlike previous experiments, no precursor oscillation has been observed. 相似文献
93.
Cristoni S Cuccato D Sciannamblo M Bernardi LR Biunno I Gerthoux P Russo G Weber G Mora S 《Rapid communications in mass spectrometry : RCM》2004,18(1):77-82
Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder mainly caused by 21-hydroxylase deficit (21-OHD). Deletions or mutations of the CYP21 gene induce the impairment of glucocorticoid and mineralcorticoid synthesis. 17-Hydroxyprogesterone (17-OHP) is the hormonal marker in patients, but not in the heterozygous subjects. Excess 17-OHP is hydroxylated into 21-deoxycortisol (21-DF), and therefore 21-DF can be used as a specific marker for diagnosis of heterozygous individuals. We report an analytical method for analysis of 21-DF in blood samples using electrospray (ESI) and atmospheric pressure chemical ionization (APCI), showing that ESI is very sensitive for the analysis of this marker molecule. The multiple reaction monitoring (MRM) approach was used to increase the specificity and the sensitivity of the method. 相似文献
94.
Ohyabu N Ida K Morisaki T Narihara K Komori A Watanabe K Narushima Y Nagayama Y Shoji M Ashikawa N Emoto M Funaba H Goto M Idei H Ikeda K Inagaki S Inoue N Isobe M Khlopenkov K Kobuchi T Kostrioukov A Kubo S Kumazawa R Liang Y Masuzaki S Minami T Miyazawa J Morita S Muto S Mutoh T Murakami S Nakamura Y Nakanishi H Nishimura K Noda N Notake T Ohkubo K Ohdachi S Oka Y Osakabe M Ozaki T Peterson BJ Sakamoto R Sakakibara S Sagara A Saito K Sasao M Sato K Sato M Seki T Shimozuma T Sudo S Suzuki H 《Physical review letters》2002,88(5):055005
In the Large Helical Device plasma discharges, the size of an externally imposed island with mode number ( n/m = 1/1) decreases substantially when the plasma is collisionless ( nu(*)< approximately 1) and the beta is finite ( > approximately 0.1%) at the island location. For the collisional plasmas with finite beta, on the other hand, the size of the island increases. However, there is a threshold in terms of the vacuum island size below which the island enlargement is not seen. 相似文献
95.
Nonradiative deactivation processes of excited aniline and its derivatives in aqueous solution were investigated by steady-state and time-resolved fluorescence measurements to reveal characteristic solvent effects of water on the relaxation processes of excited organic molecules. The magnitude of nonradiative rate (knr) of excited aniline derivatives increased significantly in water compared to that in organic solvents (cyclohexane, ethanol, and acetonitrile). The fluorescence lifetime measurements in organic solvent/H2O mixed solvents suggested that the fluorescence quenching in water was not due to exciplex formation but due to interactions with a water cluster. From temperature effect experiments on the fluorescence lifetime and quantum yield of aniline, N-methylaniline, and N,N-dimethylaniline, the apparent activation energies for the nonradiative deactivation rate in water were determined as 21, 30, and 41 kJ mol-1, respectively. Upon substitution of hydrogen atoms in the aromatic ring of aniline derivatives for deuterium atoms resulted in normal deuterium isotope effect in cyclohexane, i.e. knr decreased by deuterium substitution, while in water the same deuterium substitution led to an increase in knr (the inverse isotope effect). The inverse isotope effects implied that a direct internal conversion to vibrationally higher excited states in the electronically ground state is not a dominant mechanism but the transition to a close-lying energy level, e.g. the relaxation to charge transfer to solvent (ctts) state, would be associated with the quenching mechanism in water. 相似文献
96.
Armin T. Exner Ida Pavlichenko Daniela Baierl Morten Schmidt Gerald Derondeau Bettina V. Lotsch Paolo Lugli Giuseppe Scarpa 《Laser \u0026amp; Photonics Reviews》2014,8(5):726-733
An innovative integrated sensing platform for the detection of various chemical analytes via translating the photonic stop‐band shift of a one‐dimensional photonic crystal (PC) into an electrical current change is proposed. The miniaturized sensing platform features an organic light‐emitting diode (OLED) as a light source and an organic photodetector (OPD) as a light sensor and allows for the detection of ethanol vapor concentrations down to ≈ 10 parts per million (ppm) in nitrogen, which corresponds to a stop‐band shift of ≈ 27 pm. The resolution of the proposed platform exceeds the capabilities of most commercial spectrometers and by far the human eye, while, at the same time, such a sensor is less expensive and less power consuming than a spectrometer. The presented setup is generic and can detect optical changes in the transmission of PCs, which can be induced by both vapor adsorption or by a liquid analyte, as demonstrated with a microfluidic setup. 相似文献
97.
Diego Colombo Fiamma Ronchetti Antonio Scala Ida M. Taino Piera A. Taino 《Journal of carbohydrate chemistry》2013,32(4):611-617
Abstract An efficient chemoenzymatic synthesis of methyl α-d-allopyranoside and methyl 3-deoxy-α-d-ribo-hexopyranoside starting from methyl 4,6-O-benzylidene-α-d-glucopyranoside is described. 相似文献
98.
This paper reviews the application of a modification of the polarographic Brdi?ka method for cancer testing. The modification comprises the catalytic electroreduction of metal ions (here called Brdi?ka method based on catalytic metal ion reduction for cancer testing—BMMCT) and/or the electrooxidation of proteins, instead of the classical approach based on the catalytic electroreduction of protons, i.e., hydrogen waves (here called Brdi?ka method based on catalytic hydrogen evolution for cancer testing—BMHCT). Further, in the modified method, the mercury electrode has been replaced by a nontoxic solid electrode and the entire measuring system has been automated. The modified method excels in improved testing rates and sensitivity of cancer testing. The cancer testing of vaginal secretions is characterized by high specificity as well. 相似文献
99.
Rituparna Biswas Yumi Ida Dr. Michael L. Baker Saptarshi Biswas Paramita Kar Prof. Dr. Hiroyuki Nojiri Prof. Dr. Takayuki Ishida Prof. Dr. Ashutosh Ghosh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(12):3943-3953
Three new trinuclear nickel (II) complexes with the general composition [Ni3L3(OH)(X)](ClO4) have been prepared in which X=Cl? ( 1 ), OCN? ( 2 ), or N3? ( 3 ) and HL is the tridentate N,N,O donor Schiff base ligand 2‐[(3‐dimethylaminopropylimino)methyl]phenol. Single‐crystal structural analyses revealed that all three complexes have a similar Ni3 core motif with three different types of bridging, namely phenoxido (μ2 and μ3), hydroxido (μ3), and μ2‐Cl ( 1 ), μ1,1‐NCO ( 2 ), or μ1,1‐N3 ( 3 ). The nickel(II) ions adopt a compressed octahedron geometry. Single‐crystal magnetization measurements on complex 1 revealed that the pseudo‐three‐fold axis of Ni3 corresponds to a magnetic easy axis, being consistent with the magnetic anisotropy expected from the coordination structure of each nickel ion. Temperature‐dependent magnetic measurements indicated ferromagnetic coupling leading to an S=3 ground state with 2J/k=17, 17, and 28 K for 1 , 2 , and 3 , respectively, with the nickel atoms in an approximate equilateral triangle. The high‐frequency EPR spectra in combination with spin Hamiltonian simulations that include zero‐field splitting parameters DNi/k=?5, ?4, and ?4 K for 1 , 2 , and 3 , respectively, reproduced the EPR spectra well after a anisotropic exchange term was introduced. Anisotropic exchange was identified as Di,j/k=?0.9, ?0.8, and ?0.8 K for 1 , 2 , and 3 , respectively, whereas no evidence of single‐ion rhombic anisotropy was observed spectroscopically. Slow relaxation of the magnetization at low temperatures is evident from the frequency‐dependence of the out‐of‐phase ac susceptibilities. Pulsed‐field magnetization recorded at 0.5 K shows clear steps in the hysteresis loop at 0.5–1 T, which has been assigned to quantum tunneling, and is characteristic of single‐molecule magnets. 相似文献
100.
Marco Cicalese Emanuele Nunzio Spadaro Caterina Ida Zeppieri 《Calculus of Variations and Partial Differential Equations》2011,41(1-2):127-150
We study the asymptotic behavior, as ${\varepsilon}$ tends to zero, of the functionals ${F^k_\varepsilon}$ introduced by Coleman and Mizel in the theory of nonlinear second-order materials; i.e., $$F^k_\varepsilon(u):=\int\limits_{I} \left(\frac{W(u)}{\varepsilon}-k\,\varepsilon\,(u')^2+\varepsilon^3(u'')^2\right)\,dx,\quad u\in W^{2,2}(I),$$ where k?>?0 and ${W:\mathbb{R}\to[0,+\infty)}$ is a double-well potential with two potential wells of level zero at ${a,b\in\mathbb{R}}$ . By proving a new nonlinear interpolation inequality, we show that there exists a positive constant k 0 such that, for k?<?k 0, and for a class of potentials W, ${(F^k_\varepsilon)}$ ??(L 1)-converges to $$F^k(u):={\bf m}_k \, \#(S(u)),\quad u\in BV(I;\{a,b\}),$$ where m k is a constant depending on W and k. Moreover, in the special case of the classical potential ${W(s)=\frac{(s^2-1)^2}{2}}$ , we provide an upper bound on the values of k such that the minimizers of ${F_\varepsilon^k}$ cannot develop oscillations on some fine scale and a lower bound on the values for which oscillations occur, the latter improving a previous estimate by Mizel, Peletier and Troy. 相似文献