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91.
合成了氯代1-(2-羟乙基)-3-甲基咪唑离子液体[He MIM]Cl、溴代1-乙胺基-3-甲基咪唑离子液体[Ae MIM]Br和氯代1-羧乙基-3-甲基咪唑离子液体[Ce MIM]Cl 3种功能化咪唑离子液体,并分别进行了红外与氢核磁结构表征.然后用3种离子液体液化木粉,液化3 h后向体系直接加入苯酚、甲醛和氢氧化钠,制备酚醛复合材料,并采用FTIR、XRD、DSC和SEM对酚醛复合材料进行结构、性能与形貌测试,研究离子液体种类对木粉液化率及酚醛树脂性能的影响.结果表明,离子液体及其液化木粉产物制备的酚醛复合材料性能得到明显改善.[Ce MIM]Cl液化效果最好,90℃液化率高达24.6%,当[Ce MIM]Cl与木粉质量比为10∶1时,制备的酚醛复合材料的游离醛释放量由原来的3.64%降低到0.92%.离子液体[Ae MIM]Br能将酚醛复合材料的冲击强度由原来的0.93 k J/m2提高到6.96 k J/m2,而[Ae MIM]Br及其液化的木粉产物制备的酚醛复合材料拉伸强度从原来的3.28 MPa提高到9.70 MPa. 相似文献
92.
S. Munavalli D. K. Rohrbaugh G. W. Wagner F. R. Longo H. D. Durst 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):781-789
Microwave catalyzed reaction of a neat mixture of styrene oxide and H-dimethylphosphonate furnished dimethyl methylphosphonate, trimethylphosphate, phenylacetaldehyde, 1-methoxy-2-phenylethanol, 1-phenylethleneglycol, cis- and trans-1,3-diphenylcyclobutanes, hydrogen 1-(2-phenylethyl)methylphosphinate, (1-phenylethyl)dimethylphosphonate, and (1-phenylethyl)dimethylphosphonate via free radical processes. 相似文献
93.
The functional equation defining the free cumulants in free probability is lifted successively to the noncommutative Faà di Bruno algebra, and then to the group of a free operad over Schröder trees. This leads to new combinatorial expressions, which remain valid for operator-valued free probability. Specializations of these expressions give back Speicher's formula in terms of noncrossing partitions, and its interpretation in terms of characters due to Ebrahimi-Fard and Patras. 相似文献
94.
《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2107-2110
Alcohols were oxidized to their corresponding carbonyl compounds with KBrO 3 in the presence of silica chloride and wet SiO 2 , in solution and under solvent free conditions. 相似文献
95.
R. Otto P. Hecht H.-G. Könnecke H. Koch H. J. Naumann W. Winzer 《Isotopes in environmental and health studies》2013,49(12):425-429
This paper reviews ways in which radioactive tracer techniques can he used to improve the efficiency of a caprolactam production plant, Residence time spectra and material distributions in different parts of the plant were measured by application of sodium 24, bromine 82 and technetium 99m. The investigations led to improved cumeneoxidators and gave useful informations on the catalytic decomposition of the phenolic tar and the hydrogenation process of phenol. It could he shown that the construction of the lactam extractor must he varied and the results of the tracerexperiments made in the distillation unit contributed to a higher quality of the final product. 相似文献
96.
Luca Deseri Mario Di Paola Massimiliano Zingales 《International Journal of Solids and Structures》2014
Complex materials, often encountered in recent engineering and material sciences applications, show no complete separations between solid and fluid phases. This aspect is reflected in the continuous relaxation time spectra recorded in cyclic load tests. As a consequence the material free energy cannot be defined in a unique manner yielding a significative lack of knowledge of the maximum recoverable work that can extracted from the material. The non-uniqueness of the free energy function is removed in the paper for power-laws relaxation/creep function by using a recently proposed mechanical analogue to fractional-order hereditariness. 相似文献
97.
This paper reports ultrasound-assisted optical imaging of chemiluminescent probes in biological tissue. A focused low power ultrasound sonochemically enhances a peroxyoxalate chemiluminescence (CL) that involves indocyanine green (ICG) as luminescent pigments. By scanning the focus, it produces tomographic images of CL in scattering media. The authors demonstrate imaging using a slab of porcine muscle measuring 50 × 50 × 75 mm, in which a capsuled CL reagent is embedded at 25 mm depth. Spatial resolution of imaging and concentration characteristics of CL reagents to enhanced CL intensity are also studied to evaluate the potential for use in bio-imaging applications with exploring the CL enhancement mechanisms. CL enhancement ratio, defined as the ratio of ultrasonically enhanced CL intensity to the base intensity without ultrasound irradiation, was found to be constant even in varying ICG and oxidizer concentrations, implying to be applicable for quantitative determination of these molecules. 相似文献
98.
Nariman M. A. Nahas 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2327-2335
Thermal fragmentation of O-Aryl-N,N-diphenylhydroxylamines I and II were investigated. Neat heating in an atmospheric nitrogen afforded arenes, biaryl, diaryl sulfide, diphenylamine, diaryl sulfone, phenols, arenesulfonic acid, carbazole, and thianthrene. In the presence of isoquinoline as a radical trap, I gave 1-phenylisoquinoline as well as the previous products. Analogous results were obtained on heating of I in boiling tetraline, which lead to the formation of 1-hydroxytetraline, α -tetralone, and 1,1′-bitetralyl as the major products. A free-radical mechanism has been postulated to take place through the initial homolysis of N─O and S─O bonds to account for the identified products. 相似文献
99.
In order to ascertain the effect of a donor monomer, vinyl acetate (VAc), on the graft copolymerization of acceptor monomers, ethyl acrylate (EA) and butyl acrylate (BA), grafting of mixed vinyl monomers (EA + VAc) and (BA + VAc) was carried out on Himachali wool in aqueous medium using ceric ammonium nitrate (CAN) as a redox initiator. Graft copolymerization was carried out at different temperatures for various reaction periods. Percent grafting and percent efficiency were determined as functions of 1) concentration of mixed vinyl monomers, 2) concentration of CAN, 3) concentration of HNO3 4) temperature, and 5) reaction time. VAc, the donor monomer, was found to decrease percent grafting of EA and BA onto wool. 相似文献
100.
A previously unreported copolymer between furan and maleic anhydride was readily obtained by free radical initiation of benzene solutions of the comonomers. The product copolymers exhibit remarkably uniform composition regardless of monomer feed ratios. A donor-acceptor complex was suspected to account for the 1:1 alternating sequence of the monomers in the product. The complex was easily detected and partially characterized, although its exact role in the mechanism is uncertain. 相似文献