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41.
太阳红外光谱中蕴含着丰富的物理信息,其中CO 4.6μm波段是具有代表性的分子谱带,其形成于温度极小区附近,对研究太阳物理具有极其重要的意义。为获得CO 4.6μm波段太阳单色像,本文建立了一套全反射太阳红外成像观测系统。该系统采用定天镜跟踪引光,通过成像反射镜将太阳成像于3~5μm波段红外相机的焦平面上,该相机采用的是国产HgCdTe焦平面阵列器件。同时,为提高信噪比,提出了一种有效计算平场提取观测目标的方法,并利用该方法获得了CO 4.6μm波段的太阳单色像。 相似文献
42.
Rabindra N. Roy Lakshmi N. Roy Jason G. Grant Mason P. Cummins Bennett J. Tabor III Sarah J. Richards Curtis A. Himes Bret R. Lively Penny L. Blackwell Ashley N. Simon 《Journal of solution chemistry》2002,31(11):861-872
The values of the second dissociation constant, pK
2, for the dissociation of the NH+ charge center of the zwitterionic buffer compounds 4-(N-morpholino)butanesulfonic acid (MOBS), and N-(2-hydroxyethyl)piperazine-Nmg src="/content/m852081303687762/xxlarge8242.gif" alt="prime" align="BASELINE" BORDER="0">-4-butanesulfonic acid (HEPBS) have been determined from 5 to 55°C, including, 37°C at intervals of 5°C. The electromotive-force (emf) measurements have been made utilizing hydrogen electrodes and silver–silver chloride electrodes. The value of pK
2 for MOBS was found to be 7.702 ± 0.0005, and 8.284 ± 0.0004 for HEPBS, at 25°C, respectively. The related thermodynamic quantities, mg src="/content/m852081303687762/xxlarge916.gif" alt="Delta" align="BASELINE" BORDER="0"> G
o, mg src="/content/m852081303687762/xxlarge916.gif" alt="Delta" align="BASELINE" BORDER="0"> H
o, mg src="/content/m852081303687762/xxlarge916.gif" alt="Delta" align="BASELINE" BORDER="0"> S
o, and mg src="/content/m852081303687762/xxlarge916.gif" alt="Delta" align="BASELINE" BORDER="0"> C
p
o for the dissociation processes of MOBS and HEPBS have been derived from the temperature coefficients of pK
2. Both the MOBS and HEPBS buffer materials are useful as primary pH standards for the control of pH 7.3 to 8.6 in the region close to that of physiological fluids. 相似文献
43.
Composite membranes were prepared by (a) infiltrating NAFIONmg src="/content/n16m8vq47r0670g1/xxlarge8482.gif" alt="trade" align="BASELINE" BORDER="0"> with SiO2-P2O5-ZrO2 sol, and (b) recasting a film using NAFIONmg src="/content/n16m8vq47r0670g1/xxlarge8482.gif" alt="trade" align="BASELINE" BORDER="0"> solution containing SiO2-P2O5-ZrO2 sol. The membranes were characterized by Differential Thermal Analysis and ac-impedance spectroscopy as a function of relative humidity. The influences of the heat treatment (80°C–150°C) and cleaning on the electrical properties were investigated. The incorporation of SiO2-P2O5-ZrO2 gels into NAFIONmg src="/content/n16m8vq47r0670g1/xxlarge8482.gif" alt="trade" align="BASELINE" BORDER="0"> lead to improvements in its thermal stability and proton conductivity. 相似文献
44.
Kenzo Sato 《International Journal of Infrared and Millimeter Waves》1986,7(6):927-947
Under the influence of perpendicularly applied positive electro-static field less than mg src="/content/q622g78u425611m0/xxlarge8776.gif" alt="ap" align="MIDDLE" BORDER="0">103V/cm to silk fibron textiles, at the high frequency side of the C2–O bending reflection band (mg src="/content/q622g78u425611m0/xxlarge8776.gif" alt="ap" align="MIDDLE" BORDER="0">450mg src="/content/q622g78u425611m0/xxlarge8764.gif" alt="sim" align="MIDDLE" BORDER="0">350 cm–1), effect of step creation and step annihilation of the C2–O pseudo dending bands was induced in three stages at mg src="/content/q622g78u425611m0/xxlarge8776.gif" alt="ap" align="MIDDLE" BORDER="0">600mg src="/content/q622g78u425611m0/xxlarge8764.gif" alt="sim" align="MIDDLE" BORDER="0">450 cm–1 region IR spectroscopically relating to the stepnized statistical transfer of the unbonded 2P2, mg src="/content/q622g78u425611m0/xxlarge960.gif" alt="pgr" align="BASELINE" BORDER="0"> electrons in carbon which present with density of mg src="/content/q622g78u425611m0/xxlarge8776.gif" alt="ap" align="MIDDLE" BORDER="0">4.0×1014/cm2 in the surface mono-layer of silk fibroin from the states formed in (–C1–C2–N–)m spiral chains upto the pseudo-bending states formed in C2–O bondings. Fine mg src="/content/q622g78u425611m0/xxlarge8776.gif" alt="ap" align="MIDDLE" BORDER="0">90 steps measured overlapping on these four types of C2–O reflection bands were analysed as to consist four step series and they were shown as,y = A·Jm + B cm–1 with A=20, B=521, m=0.55 and J=1, 2...18 for the B-series.And with A=39, B=283, m=0.63 and J=1, 2 ...17 for the C-series.y
J = A·J + B cm–1 with A=11.42, B=201 and J=1, 2...13, for the D-series. And, stepnized C2–O bending bands including that of permanent oscillators and pseudo-bending oscillators induced by the effect of transfer of the unbonded 2P2 electrons in carbon atoms were shown as, EN=A·N2+B·N+C (eV) with A=–1.50×10–3, B=1.65×10–2 and C=2.4×10–2. 相似文献
45.
ab initio Calculation of the Cl2C=CHOMe molecule has been carried out with geometrical optimization in the split valence basis set in the RHF/6-31G*//RHF/6-31G* approximation. An analysis of the populations of the p-orbitals of the Cl atoms implies the absence of p,mg src="/content/m885386139465882/xxlarge960.gif" alt="pgr" align="BASELINE" BORDER="0">-conjugation between the unshared electron pairs of these atoms and the mg src="/content/m885386139465882/xxlarge960.gif" alt="pgr" align="BASELINE" BORDER="0">-bond. The asymmetry parameters of the electric field gradient at the35Cl nuclei, calculated from the 3p-orbital populations of the Cl atoms, practically coincide with the experimental values.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2369–2372, December, 1995.The authors are grateful to G. S. Beloglazov for assistance in accomplishingab initio calculations. 相似文献
46.
Itsuo Furuoya 《Catalysis Surveys from Japan》1999,3(1):71-73
The vapor phase catalytic reaction between aromatic carboxylic acid and acetic acid was investigated. Many metal oxides catalyzed the reaction between 2mg src="/content/m1274j4038230616/xxlarge8208.gif" alt="dash" align="MIDDLE" BORDER="0">methylbenzoic acid (OTA) and acetic acid (AA) to produce 2mg src="/content/m1274j4038230616/xxlarge8208.gif" alt="dash" align="MIDDLE" BORDER="0">methylacetophenone (OMA), and weakly acidic oxides such as Th, U, Ce, and La oxide exhibited higher yield of OMA. The OMA yield depended on the catalyst support. SiO2, Al2O3, TiO2, and ZrO2 with a surface area of less than 200 m2 g–1 appeared to be suitable as industrial catalyst supports. CeO2 on Al2O3was chosen as an industrial catalyst for the synthesis of OMA because of higher productivity, longer catalyst life, and lifting of legal restrictions on catalyst handling. This catalyst system can also be applied to the syntheses of acetophenone, nitroacetophenone, and chloroacetophenone. 相似文献
47.
Eberhard Hohaus 《Monatshefte für Chemie / Chemical Monthly》1980,111(4):863-875
The i.r., u. v.,1H n.m.r.,13C n.m.r., and11B n.m.r. spectra of several substituted diphenylboron chelates derived from salicylaldehyde azomethines were compared with respect to the influence of the amine substituentR. O–B–N-6-ring constitution of the chelates29–32 [R=OH, NH2, NHC6H5, N(CH3)2] can be deduced from the spectra.
Als 3. Mitt. gilt:F. Umland undE. Hohaus mit Beiträgen vonW. Riepe, K. Brodte, C. Schleyerbach undD. Szonn. Untersuchungen über borhaltige Ringsysteme vom Chelattyp. Forschungsbericht des Landes Nordrhein-Westfalen Nr. 2538. Opladen: Westdeutscher Verlag. 1976. 相似文献
48.
49.
Preparation, Properties and Crystal Structure of Bis(phthalocyaninato)cerium(IV) The anodic or chemical oxidation with dibenzoylperoxide of solutions of bis(phthalocyaninato)cerate(III) in dichloromethane yields selectively sparely soluble bis(phthalocyaninato)cerium(IV), [Ce(Pc(2-)) 2 ]. Green, monoclinic needles cristallize with a = 18.783(12) Å b = 18.739(16) Å c= 15.618(10) Å ß114.30(7)°; Z = 4; space group C2/c. [Ce(Pc(2–)) 2 ] is a sandwich complex in which the cerium Atom is eightfold coordinated by the isoindole nitrogens of the two staggered convex Pc-rings. The u.v.-vis., m.i.r., f.i.r. and resonance Raman spectra are consistent with the structure. 相似文献
50.
Péter Pulay 《Theoretical chemistry accounts》1979,50(4):299-312
An ab initio Hartree-Fock gradient program is described. It is characterized by (1) efficiency of the gradient evaluation, and (2) capability of handling higher angular momentum (d andf) basis functions. The latter are constructed from shifted Cartesian Gaussian p-type primitives. A satisfactory solution is presented for the problems connected with the neglect of small integrals in a gradient program. Methods for increasing the efficiency of the SCF procedure are discussed. 相似文献