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1.
Alick KT Law Deepak Gupta Shawn Levy Douglas C Wallace Robert J McKeon Charles R Buck 《BMC neuroscience》2004,5(1):1
Background
The adenine nucleotide translocator 1 (Ant1) is an inner mitochondrial membrane protein involved with energy mobilization during oxidative phosphorylation. We recently showed that rodent Ant1 is upregulated by transforming growth factor-beta (TGF-β) in reactive astrocytes following CNS injury. In the present study, we describe the molecular mechanisms by which TGF-β1 regulates Ant1 gene expression in cultured primary rodent astrocytes. 相似文献2.
The Crystal and Molecular Structure of N,N′-Bis(trimethylsilyl) Oximidic Acid Bis (trimethylsilyl) Ester The X-ray structure analysis of the reaction product of oxalyl chloride with sodium bis(trimethylsilyl) amide formulated by PUMP and ROCHOW as N,N′-bis(trimethylsilyl) oximidic Acid bis (trimethylsilyl) ester shows that the suggested structure is correct for the solid state. The compound crystallizes in the space group P1 with a = 9.948(4), b = 6.612(3), c = 10.370(4) Å, α = 88.87(6), β = 116.95(4), γ = 98.23(6)°, and Z = 1. The molecule manifests symmetry 1 . 相似文献
3.
Jens O BunteStefanie Rinne Christian SchäferBeate Neumann Hans-Georg StammlerJochen Mattay 《Tetrahedron letters》2003,44(1):45-48
PET oxidative cyclization of silyl enol ethers carrying suitable side chains with olefinic double bonds results in the stereoselective formation of carbocycles. Two model compounds for investigating the influence of silyl enol ether ring size are synthesized. Furthermore the synthesis of a quasi-steroidal carbocycle with an unnatural configuration is presented. 相似文献
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Michael Zech Matthias Saurer Mario Tuthorn Katja Rinne Roland A. Werner Rolf Siegwolf 《Isotopes in environmental and health studies》2013,49(4):492-502
Although the instrumental coupling of gas chromatography-pyrolysis-isotope ratio mass spectrometry (GC-Py-IRMS) for compound-specific δ18O analysis has been commercially available for more than a decade, this method has been hardly applied so far. Here we present the first GC-Py-IRMS δ18O results for trimethylsilyl-derivatives of plant sap-relevant sugars and a polyalcohol (glucose, fructose, sucrose, raffinose and pinitol). Particularly, we focus on sucrose, which is assimilated in leaves and which is the most important transport sugar in plants and hence of utmost relevance in plant physiology and paleoclimate studies. Replication measurements of sucrose standards and concentration series indicate that the GC-Py-IRMS δ18O measurements are not stable over time and that they are amount (area) dependent. We, therefore, suggest running sample batch replication measurements in alternation with standard concentration series of reference material. This allows for carrying out (i) a drift correction, (ii) a calibration against reference material and (iii) an amount (area) correction. Tests with 18O-enriched water do not provide any evidence for oxygen isotope exchange reactions affecting sucrose and raffinose. We present the first application of GC-Py-IRMS δ18O analysis for sucrose from needle extract (soluble carbohydrate) samples. The obtained δ18Osucrose/ Vienna Standard Mean Ocean Water (VSMOW) values are more positive and vary in a wider range (32.1–40.1 ‰) than the δ18Obulk/ VSMOW values (24.6–27.2 ‰). Furthermore, they are shown to depend on the climate parameters maximum day temperature, relative air humidity and cloud cover. These findings suggest that δ18Osucrose of the investigated needles very sensitively reflects the climatically controlled evaporative 18O enrichment of leaf water and thus highlights the great potential of GC-Py-IRMS δ18Osucrose analysis for plant physiology and paleoclimate studies. 相似文献
6.
Spectroscopic Studies on Sulphur Compounds. VII. 1H- and 13C-NMR Spectroscopic Investigations of Sulphinic Acid Chlorides and Chloro-sulphurous Acid Alkylesters The temperature dependent 1H- and 13C-n.m.r. spectra of the sulphinic acid chlorides R—S(O)Cl and of the chloro-sulphurous acid alkylesters RO—S(O)Cl with R = CH3CH2- and (CH3)2CH- have been measured. The differing behaviour of both nuclei is discussed in terms of inversion at the chiral sulphur atom. 相似文献
7.
Rudolf Rinne 《Fresenius' Journal of Analytical Chemistry》1938,113(7-8):241-247
Ohne Zusammenfassung 相似文献
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Privatdozent Dr. H. Rinne 《Mathematical Methods of Operations Research》1973,17(2):B13-B24
Zusammenfassung Optionale Präventivstrategien sind solche, die vorbeugende Erneuerungen nur gelegentlich eines nicht ausfallbedingten Anlagenstillstands (etwa Unterbrechungen in der Energieoder Materialversorgung, Serienumstellung, Schichtende) zulassen, ohne daß jedoch bei jeder dieser Gelegenheiten erneuert werden muß. Ein zweckmäßiges Entscheidungskriterium dafür, ob beim Eintritt einer Erneuerungsgelegenheit vorbeugend erneuert werden soll oder nicht, ist das momentane Alter der Anlage. Im einzelnen enthält der Aufsatz: 1. den Nachweis, daß es eine optionale Präventivstrategie gibt, die kostengünstiger ist als die streng periodische Präventivstrategie, 2. den Existenz-beweis einer optimalen Altersgrenze, nach deren Erreichen beim Eintritt einer Erneuerungsgelegenheit die Anlage vorbeugend zu erneuern ist, sofern die Anlage eine monoton wachsende Ausfallrate aufweist, 3. die Herleitung der Bestimmungsgleichung für die Altersgrenze bei exponentiell-verteilten Abständen zwischen den Erneuerungsgelegenheiten, 4. einen Weg zur Bestimmung der optimalen Ahersgrenze, wenn die Erneuerungsgelegenheiten äquidistant sind und 5. ein Verfahren zur approximativen Bestimmung der optimalen Altersgrenze.
Summary This paper examines a variant of the most commonly used preventative replacement policies. The improvement of these policies is brought about by the simple expedient of replacing plant after a failure, but not always replacing it when a replacement opportunity such as a breakdown in the supply of energy occurs. Such policies, where replacement is not obligatory at every opportunity, are called optional preventative policies. The best policy in this class is to replace plant at occurence of an opportunity if its age has reached a control limit, otherwise to defer replacement.The author shows that there is an optional preventative policy which is cheaper than the strictly periodic preventative policy. For plant having an increasing failure rate he proves the existence of an optimal control limit. The equation determining that control limit is given for the case where the opportunities occur at random (exponentially distributed) or are entirely regular. Finally there is given a rule of thumb for determining a good replacement rule.相似文献