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991.
Vegetative insecticidal protein (Vip), a unique class of insecticidal protein, is now part of transgenic plants for conferring
resistance against lepidopteron pests. In order to address the imminent regulatory need for detection and labeling of vip3A carrying genetically modified (GM) products, we have developed a standard single PCR and a multiplex PCR assay. As far as
we are aware, this is the first report on PCR-based detection of a vip3A-type gene (vip-s) in transgenic cotton and tobacco. Our assay involves amplification of a 284-bp region of the vip-s gene. This assay can possibly detect as many as 20 natural wild-type isolates bearing a vip3A-like gene and two synthetic genes of vip3A in transgenic plants. The limit of detection as established by our assay for GM trait (vip-s) is 0.1%. Spiking with nontarget DNA originating from diverse plant sources had no inhibitory effect on vip-s detection. Since autoclaving of vip-s bearing GM leaf samples showed no deterioration/interference in detection efficacy, the assay seems to be suitable for processed
food products as well. The vip-s amplicon identity was reconfirmed by restriction endonuclease assay. The primer set for vip-s was equally effective in a multiplex PCR assay format (duplex, triplex and quadruplex), used in conjunction with the primer
sets for the npt-II selectable marker gene, Cauliflower mosaic virus 35S promoter and nopaline synthetase terminator, enabling concurrent detection of the transgene, regulatory sequences and
marker gene. Further, the entire transgene construct was amplified using the forward primer of the promoter and the reverse
primer of the terminator. The resultant amplicon served as a template for nested PCR to confirm the construct integrity. The
method is suitable for screening any vip3A-carrying GM plant and food. The availability of a reliable PCR assay method prior to commercial release of vip3A-based transgenic crops and food would facilitate rapid and efficient regulatory compliance.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
An application for an Indian patent (1891/DEL2006/17.08.07) comprising a substantive part of this study has been filed.
ITRC communication no. 2516. 相似文献
992.
Arivozhi Mohan S. Shanmugavel Ajay Goyal B. R. Venkataraman D. Saravanan 《Chromatographia》2009,12(3)
Five impurities were observed when candesartan cilexetil tablets were subjected to stability and forced degradation studies.
These impurities were successfully isolated and characterized as desethyl candesartan cilexetil, 1N-ethyl candesartan cilexetil, 2N-ethyl candesartan cilexetil, 1N-ethyl oxo candesartan cilexetil, and 2N-ethyl oxo candesartan cilexetil. A gradient reverse phase liquid chromatography (LC) and an isocratic preparative LC method
were used to detect and isolate all five degradation products impurities simultaneously. Mass spectrometry, 1H/13C, DEPT and 2D NMR experiments were extensively utilized to characterize these impurities. Even though desethyl candesartan
cilexetil, 1N-ethyl candesartan cilexetil were 2N-ethyl candesartan cilexetil were documented in the literature as known impurities, the regioisomers 1N-ethyl oxo candesartan cilexetil and 2N-ethyl oxo candesartan cilexetil were never noticed. Single-crystal diffraction data has been used to confirm their structure
unambiguously and synthetic preparations of all known and unknown impurities were also presented. 相似文献
993.
Dr. Kartik Chandra Mondal Dr. Sudipta Roy Priv.‐Doz. Dr. Birger Dittrich Dr. Diego M. Andrada Prof. Dr. Gernot Frenking Prof. Dr. Herbert W. Roesky 《Angewandte Chemie (International ed. in English)》2016,55(9):3158-3161
Reduction of the neutral carbene tetrachlorosilane adduct (cAAC)SiCl4 (cAAC=cyclic alkyl(amino) carbene :C(CMe2)2(CH2)N(2,6‐iPr2C6H3) with potassium graphite produces stable (cAAC)3Si3, a carbene‐stabilized triatomic silicon(0) molecule. The Si?Si bond lengths in (cAAC)3Si3 are 2.399(8), 2.369(8) and 2.398(8) Å, which are in the range of Si?Si single bonds. Each trigonal pyramidal silicon atom of the triangular molecule (cAAC)3Si3 possesses a lone pair of electrons. Its bonding, stability, and electron density distributions were studied by quantum chemical calculations. 相似文献
994.
Highly Crystalline Mesoporous C60 with Ordered Pores: A Class of Nanomaterials for Energy Applications 下载免费PDF全文
Mercy R. Benzigar Stalin Joseph Hamid Ilbeygi Dr. Dae‐Hwan Park Dr. Sujoy Sarkar Dr. Goutam Chandra Prof. Siva Umapathy Prof. Sampath Srinivasan Dr. Siddulu Naidu Talapaneni Prof. Ajayan Vinu 《Angewandte Chemie (International ed. in English)》2018,57(2):569-573
Highly ordered mesoporous C60 with a well‐ordered porous structure and a high crystallinity is prepared through the nanohard templating method using a saturated solution of C60 in 1‐chloronaphthalene (51 mg mL?1) as a C60 precursor and SBA‐15 as a hard template. The high solubility of C60 in 1‐chloronaphthalene helps not only to encapsulate a huge amount of the C60 into the mesopores of the template but also supports the oligomerization of C60 and the formation of crystalline walls made of C60. The obtained mesoporous C60 exhibits a rod‐shaped morphology, a high specific surface area (680 m2 g?1), tuneable pores, and a highly crystalline wall structure. This exciting ordered mesoporous C60 offers high supercapacitive performance and a high selectivity to H2O2 production and methanol tolerance for ORR. This simple strategy could be adopted to make a series of mesoporous fullerenes with different structures and carbon atoms as a new class of energy materials. 相似文献
995.
Arjmand F Sharma GC Sayeed F Muddassir M Tabassum S 《Journal of photochemistry and photobiology. B, Biology》2011,105(3):167-174
N,N-bis[(R-/S-)-1-benzyl-2-ethoxyethane] tin (IV) complexes were synthesized by applying de novo design strategy by the condensation reaction of (R-/S-)2-amino-2-phenylethanol and dibromoethane in presence of dimethyltin dichloride and thoroughly characterized by elemental analysis, conductivity measurements, IR, ESI-MS, (1)H, (13)C and (119)Sn, multinuclear NMR spectroscopy and XRD study. Enantioselective and specific binding profile of R-enantiomer 1 in comparison to S-enantiomer 2 with ultimate molecular target CT-DNA was validated by UV-visible, fluorescence, circular dichroism, (1)H and (31)P NMR techniques. This was further corroborated well by interaction of 1 and 2 with 5'-GMP. 相似文献
996.
Sharma AK Chandra S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,81(1):424-430
Complexes of the type [M(L)X(2)], where M = Co(II), Ni(II) and Cu(II), have been synthesized with novel NO-donor Schiff's base ligand, 1,4-diformylpiperazine bis(4-imino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one) which is obtained by the acid catalyzed condensation of 1,4-diformylpiperazine with 4-aminoantipyrine. The elemental analyses, molar conductance measurements, magnetic susceptibility measurements, IR, UV, NMR, mass and EPR studies of the compounds led to the conclusion that the ligand acts as tetradentate chelate. The Schiff's base ligand forms hexacoordinated complexes having octahedral geometry for Ni(II) and tetragonal geometry for Co(II) and Cu(II) complexes. The mycological studies of the compounds were examined against the several opportunistic pathogens, i.e., Alternaria brassicae, Aspergillus niger and Fusarium oxysporum. The Cu(II) complexes were found to have most fungicidal behavior. 相似文献
997.
998.
The substituted warfarin acid chalcones have been prepared by condensation of warfarin acid and aromatic/aliphatic aldehyde using aq. NaOH as catalyst. The method is simple, cost‐effective and gives good yield in a short reaction time. All the compounds synthesized have been characterized by IR, NMR and Mass spectra. A new series of 4‐hydroxy‐3‐(3‐oxo‐1,5‐diaryl‐3‐oxo‐pent‐4‐enyl)‐chromen‐2‐ones were synthesized and submitted to biological activity. Result of the biological screening showed the compounds 3b , 3h being the most effective among the various treatments in antimicrobial screening. Compounds 3c , 3d , 3k and 3l showed moderate activity against the microorganisms tested. Compounds 3e , 3h have shown good antifungal activity. 相似文献
999.
Elucidation of the structure of hitherto unknown novel pyranobisquinoline derivatives, (7H)-6,8-Dichloro-7-methyl -pyrano(3,2-c;5,6-c′)bisquinoline 5 and (7H)-6,8-Dichloro-7-methyl-pyrano(3,2-c:5,6-b′)bisquinoline 4 obtained as unexpected products1 in the Michael type reaction of vinylacetate on 4-hydroxyquinoline-2(lH)-one 1 by NMR methods is reported. 相似文献
1000.
The use of online FT‐IR is described for investigating the degradation kinetics of the solid amorphous pharmaceutical compound, fosaprepitant dimeglumine (FD), under stress storage conditions (i.e., high temperature, T, and humidity, % RH). It is found that under conditions of elevated T and % RH, the kinetics are denucleation rate limited for the deliquescence of the amorphous FD solid, based on the high quality fits obtained to the authors' dispersive kinetic model for that mechanism. At elevated T and low % RH, it is found that a classical, first‐order hydrolysis mechanism for the degradation of FD (which forms crystalline aprepitant, AP) significantly contributes to the overall conversion rate. That mechanism is similar to the one observed previously for the solution‐phase hydrolysis of FD. Appropriate kinetic models are proposed for the FD‐to‐AP conversion under all of the experimental conditions investigated in this work. © 2009 Wiley Periodicals, Inc. Int J Chem Kinet 42: 25–36, 2010 相似文献