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481.
A reaction between 2, 8-dichloro-4, 10-dinitro-5, 11-dehydro-5H, 11H-benzotriazolo[2, 1-a]-benzotriazole 8 and sodium azide in dimethyl sulfoxide produced 3, 9-diazido-4, 10-dinitro-5, 11-dehydro-5H, 11H-benzotriazolo [2, 1-a]benzotriazole 10 rather than the 2.8-diazido isomer 9 expected by direct displacement. Thermolytic elimination of nitrogen (2 moles) converted the dinitro diazide 10 to 3,4,9,10-bisfuroxano-5, 11-dehydro-5H, 11H-benzotriazolo[2, 1-a]benzotriazole 11 that was subsequently nitrated to give the 2,8-dinitro derivative 12 . Similar nitration converted the dinitro diazide 9 to the trinitro 15 and tetranitro 14 derivatives: thermolysis of the latter gave 1,2,7,8-bisfuroxano-4, 10-dinitro-5, 11-dehydro-5H, 11H-benzotriazolo[2, 1-a]-benzotriazole 16 . Nitration (100% HNO3, CF3SO3H) converted compound 16 to the 3,4,10-trinitro derivative 17 , whereas a similar nitration (100% HNO3, FSO3H) gave the title compound BTBB, an insensitive high-energy, high-density (d 2.03 g/cc) molecule. © 1995 John Wiley & Sons, Inc. 相似文献
482.
Vayalakkavoor T. Ramakrishnan Murugappa Vedachalam Joseph H. Boyer 《Heteroatom Chemistry》1991,2(6):669-673
The 4,6-dinitroso derivative 11 was obtained (83%) by the nitrosation of 2-oxooctahydroimidazo[4,5-d]-imidazole 1 as the dihydrochloride and was converted to the 4,6-dinitro derivative 12 [66%] by treatment with nitric acid (100%, -40°C) and to the 1,4,6-trinitro derivative 13 (66%) and the 1,3,4,6-tetranitro derivative 2 (86%) by treatment with nitric acid (100%) in acetic anhydride at 0–5°C and 10–25°C respectively. Similar treatment with nitric acid (100%) in either acetic or trifluoroacetic anhydride at 0–25°C converted the trinitro compound 13 to the tetranitro compound 2 (86%). The dinitramine 12 was also obtained (43%) from the diamine 1 by nitration with nitric acid (100%, -40°C). A reaction between 2-nitrimino-5-iminooctahydroimidazo[4,5-d]imidazole 7 as a hydrochloride salt (from an acid catalyzed condensation between 4,5-dihydroxy-2-nitriminoimidazolidine 6 and guanidine) and nitric acid (100%, -40°C) gave the 2,5-dinitrimino derivative 14 (85%) isolated as a monohydrate. The nitrate salt 7 · HNO3, isomeric with 14 · H2O, was obtained from the corresponding hydrochloride 7 · HCl and silver nitrate. Both nitrimines 7 and 14 gave 1,3,4,6-tetranitro-2,5-dioxooctahydroimidazo[4,5-d]imidazole 15 (66% and 59%) by treatment with nitric acid (100%) in acetic anhydride. 相似文献
483.
Mayur Shah Kannappan Thangaraj Mou-Ling Soong Lionel T. Wolford Joseph H. Boyer Ieva R. Politzer Theodore G. Pavlopoulos 《Heteroatom Chemistry》1990,1(5):389-399
Condensations between 3-X-2,4-dimethylpyrroles (X = H, CH3, C2H5, and CO2C2H5) and acyl chlorides gave derivatives of 3,5,3′,5′-tetramethylpyrromethene (isolated as their hydrochloride salts): 6-methyl, 6-ethyl, 4,4′,6-trimethyl, 4,4′-diethyl-6-methyl, and 4,4′-dicarboethoxy-6-ethyl derivatives for conversion on treatment with boron trifluoride to 1,3,5,7-tetramethylpyrromethene–BF2 complex (TMP–BF2) and its 8-methyl (PMP–BF2), 8-ethyl, 2,6,8-trimethyl (HMP–BF2),2,6,-diethyl-8-methyl (PMDEP–BF2), and 2,6-dicarboethoxy-8-ethyl derivatives. Chlorosulfonation converted, 1,3,5,7,8-pentamethylpyrromethene–BF2 complex to its 2,6-disulfonic acid isolated as the lithium, sodium (PMPDS–BF2), potassium, rubidium, cesium, ammonium, and tetramethylammonium disulfonate salts and the methyl disulfonate ester. Sodium 1,3,5,7-tetramethyl-8-ethylpyrromethene-2,6-disulfonate–BF2 complex was obtained from the 8-ethyl derivative of TMP–BF2. Nitration and bromination converted PMP–BF2 to its 2,6-dinitro-(PMDNP–BF2) and 2,6-dibromo- derivatives. The time required for loss of fluorescence by irradiation from a sunlamp showed the following order for P–BF2 compounds (10−3 to 10−4 M) in ethanol: PMPDS–BF2, 7 weeks; PMP–BF2, 5 days; PMDNP–BF2, 72 h; HMP–BF2, 70 h; and PMDEP–BF2, 65 h. Under similar irradiation PMPDS–BF2 in water lost fluorescence after 55 h. The dibromo derivative was inactive, but each of the other pyrromethene–BF2 complexes under flashlamp excitation showed broadband laser activity in the region λ 530–580 nm. In methanol PMPDS–BF2 was six times more resistant to degradation by flashlamp pulses than was observed for Rhodamine-6G (R-6G). An improvement (up to 66%) in the laser power efficiency of PMPDS–BF2 (10−4 M in methanol) in the presence of caffeine (a filter for light <300 nm) was dependent on flashlamp pulse width (2.0 to 7.0 μsec). 相似文献
484.
Murugappa Vedachalam Vayalakkavoor T. Ramakrishnan Joseph H. Boyer 《Heteroatom Chemistry》1991,2(2):313-318
Guanidine condensed with 1,4-diformyl-2,3,5,6-tetrahydroxypiperazine 1 to give 2,6-diiminodecahydro-1H,5H-diimidazo[4,5-b:4′,5′-e]pyrazine 3 isolated as the tetrahydrochloride salt. nitric acid (100%) at −40°C converted the bisguanidine 3 to 2,6-dinitrimino-4,8-dinitrodecahydro-1H,5H-diimidazo[4,5-b:4′,5′-e]- pyrazine 8 isolated as a dihydrate, whereas nitration by nitronium tetrafluoroborate at 0° to 25°C afforded 2,6-diimino-4,8-dinitrodecahydro-1H,5H-diimidazo[4,5-b:4′,5′-e]pyrazine 9 isolate as the monohydrated bistetrafluoroborate salt, and treatmetn with nitric acid (100%) and acetic anhydride or phosphorus pentoxide converted the bisguanidine 3 to 2,6-dioxo-1,3,4,5,7,8-hexanitrodecahydro-1H,5H-diimidazo[4,5-b:4′,5′-e]pyrazine 4 , also obtained from the tetra N-nitro compound 8 · 2 H2O and from the dinitramine 9 · 2 BHF4 · H2O after similar treatment. The cis-syn-cis- configuration of the tricyclic bisurea 4 and bisguanidine 9 was confirmed by X-ray crys-tallographic analysis. Nitrosation by nitrous acid or by dinitrogen tetroxide converted the bisguanidine 3 to a hydrated 2,6-dinitrosimino-4,8-dinitrosodecahydro-1H,5H-diimidazo[4,5-b:4′,5′-]pyrazine 10 · 2.5 H2O, whereas treatment with nitrosonium tetrafluo-roborate afforded the bistetrafluoroborate salt of 4,8-dinitroso derivative 11 · 2 BHF 4 . The nitrosamines 10 and 11 were converted to the tetranitro compound 8 · 2 H2O on treatment with nitric acid (100%) at −40°C. Treatmnt with fluoroboric acid etherate in acetonitrile converted nitroimino groups in compound 8 · 2 H2O and nitrosimino groups in compound 10 · 2.5 H2O to imino groups in compounds 9 · 2 BHF2 · H2O and 11 · 2 HBF4 respectively. 相似文献
485.
Govindarao Sathyamoorthi Lionel T. Wolford Anthony M. Haag Joseph H. Boyer 《Heteroatom Chemistry》1994,5(3):245-249
Treatment with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) oxidized 2,6-diethyl-1,3,5,7,8-pentamethylpyrromethene–BF2 complex 1 , 13,14-trimethyl-2, 3, 4, 5,9,10,11,12-octahydroindomethene–BF2 complex 5 , and 1,3,5,7,8-pentamethyl-1,2,3,5,6,7-hexahydropyromethene–BF2 complex 8 to the weakly fluorescent 3-formyl, 5-oxo, and 8-formyl derivatives 4 , 6 , and 9 , respectively. The dye 1 was oxidized by lead tetraacetate to 1,7,8-trimethyl-2,6-diethyl-3,5-diacetoxymethylpyrromethene–BF2 complex 12 [λf (ethanol) 538 nm, Φ 0.62, λlas (ethanol) 555–570 nm]. Catalytic reduction (Pd/C) converted the aldehyde 4 to 2,6-diethyl-3-hydroxymethyl-1,5,7,8-tetramethylpyrromethene–BF2 complex 10 [λf (ethanol) 537 nm, Φ 0.70, λlas (ethanol) 547–575 nm]. 相似文献
486.
Kenny Lee Nathaniel Corrigan Cyrille Boyer 《Angewandte Chemie (International ed. in English)》2023,62(44):e202307329
Polymerization induced microphase separation (PIMS) is a strategy used to develop unique nanostructures with highly useful morphologies through the microphase separation of emergent block copolymers during polymerization. In this process, nanostructures are formed with at least two chemically independent domains, where at least one domain is composed of a robust crosslinked polymer. Crucially, this synthetically simple method is readily used to develop nanostructured materials with the highly coveted co-continuous morphology, which can also be converted into mesoporous materials by selective etching of one domain. As PIMS exploits a block copolymer microphase separation mechanism, the size of each domain can be tightly controlled by modifying the size of block copolymer precursors, thus providing unparalleled control over nanostructure and resultant mesopore sizes. Since its inception 11 years ago, PIMS has been used to develop a vast inventory of advanced materials for an extensive range of applications including biomedical devices, ion exchange membranes, lithium-ion batteries, catalysis, 3D printing, and fluorescence-based sensors, among many others. In this review, we provide a comprehensive overview of the PIMS process, summarize latest developments in PIMS chemistry, and discuss its utility in a wide variety of relevant applications. 相似文献
487.