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561.
Diurnal variation of blood sugar, C-peptide immunoreactivity (CPR), free insulin and total insulin were measured in 10 insulin requiring diabetics after obtaining adequate control of diabetes with commercial lente insulin treatment. Following these tests, insulin treatment were changed to monocomponent insulin (MC-insulin) from commercial lente insulin treatment in all subjects and the same tests were performed at 7th day of MC-insulin treatment. Diurnal variations of blood sugar in both groups were not changed significantly. Also changes in CPR of both groups were nearly same magnitude and endogenous insulin secretion in these insulin treated diabetics were suggested except a case of juvenile diabetic subject. However personal variation were great in diabetics with high antibody titer, diurnal variations of total extractable insulin in both groups were quite comparable. And mean diurnal changes in free insulin were resemble to that of CPR. All of these data suggested that clinical effects of MC-insulin and commercial insulin treatment on insulin requiring diabetics were comparable except insulin antibody or proinsulinspecific antibody production. 相似文献
562.
Miyabe H Yoshida K Reddy VK Matsumura A Takemoto Y 《The Journal of organic chemistry》2005,70(14):5630-5635
[reaction: see text] The viability of oximes as nucleophiles in transition-metal-catalyzed allylic substitution was examined. The oxygen atom of oxime acted as a reactive nucleophile in the reaction of a pi-allyl palladium complex. In the presence of Pd(PPh3)4, the allylic substitution of oximes with allylic carbonate afforded the linear O-allylated oxime ethers selectively without a base. In contrast, the palladium-catalyzed reaction with allylic acetate proceeded smoothly in the presence of K2CO3 or Et2Zn as a base. Selective formation of nitrones was achieved by using palladium(II) catalyst. In the presence of Pd(cod)Cl2, the allylic substitution of oximes with allylic acetate afforded the N-allylated nitrones under solvent-free conditions, as a result of the reaction with the nitrogen atom of oximes. 相似文献
563.
Asymmetric oxidation of 1,2-diols using N-bromosuccinimide in the presence of chiral copper catalyst
Osamu Onomura Hitomi Arimoto Yoshihiro Matsumura Yosuke Demizu 《Tetrahedron letters》2007,48(49):8668-8672
Asymmetric oxidation of 1,2-diols using N-bromosuccinimide (NBS) in the presence of copper(II) triflate and (R,R)-Ph-BOX has been exploited. This oxidation was applicable to asymmetric desymmetrization of meso-hydrobenzoin and kinetic resolution of dl-hydrobenzoin and racemic-cycloalkane-cis-1,2-diols to afford optically active α-ketoalcohols with good to high enantiomeric excess. 相似文献
564.
Summary The surface changes of active carbon by wet oxidation and the resulting changes in adsorptivity were studied. The oxidation of active carbon with hydrogen peroxide or nitric acid solutions caused the changes of the specific surface area from 1101 m2/g to 574 m2/g, immersional heat into water from 9.1 cal/g to 22.9 cal/g and immersional heat into ethanol from 28.4 cal/g to 18.8 cal/g. The average electrostatic field strength increased from 0 to 1.90 x 104 e. s. u./cm2 as well. Pore structure with the diameter around 14 A was partly damaged. The adsorption of water vapor and alizarin yellow and aniline dissolved in ethanol by the carbon was promoted by these oxidations whereas the adsorption of phenol, aniline and alizarin yellow from aqueous solutions were depressed.
With 8 figures and 2 tables 相似文献
Zusammenfassung Es wurden Oberflächenveränderungen von Aktivkohlen durch nasse Oxidation und die daraus resultierenden Adsorptionseigenschaften untersucht. Die Oxidation der Aktivkohle mit Wasserstoffperoxid oder Salpetersäure verminderte die spezifische Oberfläche von 1101 m2/g auf 574 m2/g, erhöhte die Benetzungswärme in Wasser von 9,1 cal/g auf 22,9 cal/g und verminderte die Benetzungswärme in Ethanol von 28,4 cal/g auf 18,8 cal/g. Die mittlere elektrostatische Feldstärke stieg gleichzeitig von 0 auf 1,90. 104 e.s.u./cm2. Die Porenstruktur mit einem Durchmesser von etwa 14 Å wurde zerstört. Durch die Oxidation wurde das Adsorptionsvermögen von Wasserdampf, Alizaringelb und Anilin in Åthanollösung verbessert, die Adsorption von Phenol, Anilin und Alizaringelb in wäßriger Lösung dagegen herabgesetzt.
With 8 figures and 2 tables 相似文献
565.
K. Ninomiya H. Sugiura T. Nakatsuka Y. Kasamatsu H. Kikunaga W. Sato T. Yoshimura H. Matsumura K. Takamiya M. K. Kubo K. Sueki A. Yokoyama Y. Hamajima T. Miura K. Nishiyama A. Shinohara 《Journal of Radioanalytical and Nuclear Chemistry》2007,272(3):661-664
The electronic X-ray energies of muonic atoms were precisely measured. The atomic number (Z) dependence of the energy difference between electronic X-rays of muonic atoms and Z-1 atoms (energy shift) was systematically investigated. The energy shifts in the low-Z region were compared with those of the high-Z region that had been obtained experimentally and theoretically in previous work. An obvious difference between these two
regions was found in the atomic-number dependence of the energy shift. We also compared the energy shifts of muonic atoms
with those of pionic atoms. 相似文献
566.
Fumika Karaki Miki Kuwada Saki Tajiri Misaki Kanda Mari Yanai Mitsuhiro Kamimura 《合成通讯》2019,49(2):212-220
Protecting groups are indispensable in organic synthesis and there is a great need for a variety of deprotection methods. Here, we investigated the scope of the application of a deprotection procedure using SO3H silica gel, which we have previously reported as a desilylation procedure. Under these conditions, -OMOM, -OSEM, -OTHP, and -OAc groups and dimethyl acetal were cleaved. Pivaloyloxy, benzyloxy and methoxy carbonyl groups remained intact and selective deprotection of TBS groups in the presence of other protecting groups was accomplished. We succeeded in cleaving an acetyl group on a secondary alcohol in a highly polar nortropine derivative. Our findings here provide another deprotection option and would be helpful in the synthesis of multifunctional compounds. 相似文献
567.
N Yamada H Takashima F Nohara T Fujinawa T Matsumura K Koizumi K Hisada 《Radioisotopes》1987,36(10):505-511
For the development of 99mTc labeled tumor seeking agents, 273 drugs and chemicals were evaluated. Agents labeled by SnCl2-HCl method were injected to rats bearing Yoshida sarcoma. Scintigrams of the rats 2 hours after injection and the excised tumor and organs placed on a plate were taken and evaluated their affinity to the tumor. Isoniazid (INH) was found to be the most useful agent as a result of this screening study. Intensive study on 99mTc-INH was subsequently performed. Another labeling method, FeSO4-H2SO4 method, was evaluated and shown to be superior in both absolute tumor uptake and tumor to muscle ratio. Uptake of 99mTc-INH to Yoshida sarcoma occurred early after injection and maintained its level until later time. On the other hand, radioactivity in the blood and muscle decreased rapidly; that is, tumor to blood and muscle ratio showed rapid increase. Other animal tumor models, mouse bearing Ehrlich tumor or Sarcoma 180, were also used to evaluate the usefulness of 99mTc-INH. The labeled agent showed good localization in these tumors too. In conclusion 99mTc-INH might be a good tumor seeking agent and further clinical trials would be warrant. 相似文献
568.
Kiichiro Matsumura Yuji Atarashi Osamu Fukumoto 《Journal of polymer science. Part A, Polymer chemistry》1971,9(2):485-496
Sodium sulfate increases the polymerization activity of the titanium(III) chloride (AA)–ethylaluminum sesquichloride system for the polymerization of propylene. The reaction of ethylaluminum sesquichloride with sodium sulfate at mild conditions isolates diethylaluminum chloride, which is responsible for the polymerization activity. The reaction of these components at severe conditions forms an organometallic compound containing sulfate, (C2H5)4Al2SO4, and this compound is a powerful activator for titanium(III) chloride. 相似文献
569.
Yanzhong Li Hiroshi Matsumura Masamichi Yamanaka Tamotsu Takahashi 《Tetrahedron》2004,60(6):1393-1400
Zirconacyclopentenes reacted with isocyanates to give aza- or oxazirconacycles which were conveniently coverted into the corresponding haloamidation products of alkynes after halogenation. 1,4-Bistrimethylsilyl substituted zirconacyclopentadiene afforded a low yield of iodoamidation product, whereas zirconium-alkyne complexes stabilized with phosphine gave the iodoamidation products in moderate yields. On the other hand, zirconacyclopentanes reacted with isocyanates to give trimerization products of isocyanate, isocyanurates. 相似文献
570.
Tomonari Kakishita Kiyoichi Matsumoto Tsuyoshi Kiyotsukuri Kenji Matsumura Masahiro Hosoda 《Journal of heterocyclic chemistry》1992,29(7):1709-1715
A photochromic spiroindolinonaphthoxazine derivative, 1,3,3-trimethyl-9′-hydroxy-spiro[indoline-2,3′(3H)- naphtho[2,1-b][1,4]oxazine] 3 was synthesized by condensation of 1,2,3,3-tetramethylindolenium iodide 1 and l-nitroso-2,7-dihydroxynaphthalene 2 . Further, two new derivatives, 5 and 7 , were prepared in good yields by the reactions of 3 with the hexafluoropropene trimer 4 and 4-[perfluoro(2-isopropyl-1,3-dimethyl-1-butenyl)-oxybenzoyl chloride 6 , respectively. Their unique structural features and property are discussed based on 1H-, 13C- and 19F nmr spectral data. 相似文献