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991.
Mohan-Kumari H. Puttananjaiah Mohan Appasaheb Dhale Vaishali Gaonkar Shradha Keni 《Applied biochemistry and biotechnology》2011,163(2):215-222
Atherosclerosis is a chronic inflammatory disease of multiple etiologies. It is associated with the accumulation of oxidized
lipids in arterial lesions leading to coronary heart disease. 3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors
(commonly known as statins) are widely used in cardiovascular disease prevention to lower the cholesterol. The antioxidant
activity of HMG-CoA reductase inhibitors was studied by lipid peroxidation inhibition assay, DPPH, and hydroxyl radical scavenging-activity
methods. The lovastatin (93%) and simvastatin (96%) showed significant action of lipid peroxidation inhibition compared to
other HMG-CoA reductase inhibitors. The DPPH radical and hydroxyl radical scavenging activity of simvastatin was 38% and 33%,
respectively. The oxidative modification of serum lipid due to reactive oxygen species causes atherosclerosis. This study
revealed the importance of lovastatin and simvastatin to prevent oxidative stress-related cardiovascular diseases. 相似文献
992.
Effect of Biosurfactants on Laccase Production and Phenol Biodegradation in Solid-State Fermentation
Zhou MF Yuan XZ Zhong H Liu ZF Li H Jiang LL Zeng GM 《Applied biochemistry and biotechnology》2011,164(1):103-114
The effects of two biosurfactants, tea saponin (TS) and rhamnolipid (RL), on the production of laccase and the degradation
of phenol by P. simplicissimum were investigated in solid-state fermentation consisting of rice straw, rice bran, and sawdust. Firstly, the effects of phenol
on the fermentation process were studied in the absence of surfactants. Then, a phenol concentration of 3 mg/g in the fermentation
was selected for detailed research with the addition of biosurfactants. The results showed that TS and RL at different concentrations
had stimulative effects on the enzyme activity of laccase. The highest laccase activities during the fermentation were enhanced
by 163.7%, 68.2%, and 23.3% by TS at concentrations of 0.02%, 0.06%, and 0.10%, respectively. As a result of the enhanced
laccase activity, the efficiency of phenol degradation was also improved by both biosurfactants. RL caused a significant increase
of fungal biomass in the early stage of the fermentation, while TS had an inhibitory effect in the whole process. These results
indicated that RL could mitigate the negative effects of phenol on fungal growth and consequently improve laccase production
and phenol degradation. TS was potentially applicable to phenol-polluted solid-state fermentation. 相似文献
993.
Wetting behavior of a polymer resin used as matrix on fabric surfaces is one of the key attributes for making high quality
structural composites. Though incorporation of various functionalized nanoparticles can stimulate improvements to many properties
of epoxy resins, there has not been any report on wettability of any nano-modified epoxy on rough inclined fabric surfaces.
In this research work, wetting behavior of a previously developed nano-epoxy resin modified by a type of reactive graphitic
nanofibers (r-GNFs) was investigated. The observation results revealed that a unique wetting behavior was discovered from
the nano-epoxy on rough fabric surfaces due to the contribution of the r-GNFs. Based on this dramatically improved wettability
of the epoxy, a concept of dry–wet contact model was proposed to interpret the different wetting phenomenon observed from
the nano-epoxy and that of the pure epoxy. The improved wetting characteristics of the nano-epoxy system will be essential
for enabling future energy efficient infusion processing for manufacturing high quality and high-performance structural composite
applications. 相似文献
994.
Metallosurfactant complexes of the type trans- [Co(DH)2(HA)X], where DH = Dimethyl glyoxime, HA = Hexadecyl amine and X = Cl−, Br−, I−, N3
−, NO2
− or SCN−, were synthesized and characterized by physico-chemical and spectroscopic methods. In addition, the single crystal X-ray
structure of the ionic complex trans-[Co(DH)2(HA)2][Co(DH)2(I)2)] is presented. The critical micelle concentration values of the complexes in ethanol were obtained by measuring the absorption
at 290 nm. Specific conductivity data (at 303–313 K) served for the evaluation of the thermodynamics of micellization
) \left( {\Updelta G^{0}_{{{\text{m}}}}, \Updelta H^{0}_{{{\text{m}}}}, \Updelta S^{0}_{\text{m}} } \right) . Steady-state photolysis, cyclic voltammetry and biological activities of the complexes were studied. The compounds were
tested for antimicrobial activity. 相似文献
995.
Hui-Lu Wu Ke Li Tao Sun Fan Kou Fei Jia Jing-Kun Yuan Bin Liu Bao-Liang Qi 《Transition Metal Chemistry》2011,36(1):21-28
Tris(N-methylbenzimidazol-2-ylmethyl)amine (Mentb) and its two complexes, [Mn(Mentb)(DMF)(H2O)](pic)2
1 and [Zn(Mentb)(pic)](pic) 2 (pic = picrate), have been synthesized and characterized by physico-chemical and spectroscopic methods. Single crystal X-ray
diffraction revealed that the two complexes have different structures. In complex 1, the coordination sphere around Mn(II) is distorted octahedral, whereas in complex 2 the coordination sphere around Zn(II) is distorted trigonal bipyramidal. The DNA-binding properties of the free ligand and
its two complexes have been investigated by electronic absorption, fluorescence, and viscosity measurements. The results suggest
that the ligand and its two complexes bind to DNA via an intercalation binding mode, and their binding affinity for DNA follows
the order 1 > 2 > ligand. 相似文献
996.
Abstract
A tetrazole-supported polymeric ligand has been synthesized. The palladium complex derived from the polymeric material has been evaluated as a catalyst for the Heck reaction of aryl iodides and bromides with styrene to provide the corresponding products in high yields. The reaction proceeded smoothly in the presence of 1 mol% with respect to Pd of catalyst in DMF at 125 or 140 °C within 1–3 h. Recycling studies showed that the catalyst can be readily recovered and reused for several times without significant loss of catalytic activity. 相似文献997.
Iwona Łakomska Anna Kaźnica Romana Joachimiak Andrzej Marszałek Jerzy Sitkowski Lech Kozerski Tomasz Drewa 《Chemical Papers》2011,65(3):308-314
A novel platinum(IV) coordination compound with 6-mercaptopurine (6-Hmp) has been synthesised and characterised by IR and
NMR spectroscopy. Spectroscopic parameters indicate the presence of two chelate (S-6, N-7) monodeprotonated ligands and two
chloride ions in the coordination sphere of [PtCl2(6-mp)2] · H2O (I). Two Pt(IV) coordination compounds, [PtCl2(6-mp)2] · H2O (I) and [PtCl4(dbtp)2] (II), were used in the in vivo test against B16 mouse melanoma tumours. Cytotoxic activity of compound II against the tumour cells was found to be high (LC10 = 2.6 μM, LC50 = 17.0 μM, LC90 = 58.0 μM) compared to that of cisplatin. 相似文献
998.
Phase-separation and distribution of phenyl groups for PhTES-TEOS coatings prepared on polycarbonate substrate 总被引:1,自引:0,他引:1
Yutaka Mizuta Yusuke Daiko Atsushi Mineshige Masafumi Kobune Tetsuo Yazawa 《Journal of Sol-Gel Science and Technology》2011,58(1):80-84
Phenyltriethoxysilane (PhTES) and tetraethoxysilane (TEOS) coatings [xPhTES·(100 − x)TEOS (mol%)] (x = 0 − 80) were prepared on polycarbonate (PC) substrate, and adhesion, surface hardness and distribution of phenyl groups
were studied. The coatings with more than 60 mol% of PhTES showed good adhesion (≈ 100%), and the pencil hardness of PC substrate
(4B) improved to 2B or B after the coatings. Bulk gels with the same compositions were also prepared, and distribution of
phenyl groups were estimated using fourier transform infrared (FT-IR) spectroscopy (KBr method for bulk gels and attenuated
total reflection (ATR) method for coatings). A significant difference for the distribution of phenyl groups was clearly observed
between bulk gels and coatings, suggesting PC substrate affects the distribution of phenyl groups in coatings. The adhesion
and FTIR results revealed that there is an interaction caused by π-electrons between benzene rings on PC substrate and phenyl
groups of PhTES-TEOS coatings. It was found that the adhesion was strongly correlated with the phenylsilsesquioxane networks
formed around PC substrate side. 相似文献
999.
The interactions between pentachlorophenol (PCP) and jack bean urease were studied using UV/vis absorption, CD, fluorescence,
synchronous fluorescence, and three-dimensional fluorescence spectroscopic techniques. The fluorescence data showed that the
fluorescence quenching of urease by PCP the results of the formation of a PCP–urease complex involving a hydrophobic interaction.
The distance r between the donor (urease) and acceptor (PCP) was obtained from the fluorescence resonance energy transfer. The effect of
PCP on the conformation of urease was analyzed using UV/vis absorption, synchronous fluorescence and three-dimensional fluorescence
spectroscopic techniques. The result showed that PCP can enter into the hydrophobic pocket at the interface of urease and
that the micro environments around the tyrosine and tryptophan residues were changed. 相似文献
1000.
Franco Cataldo Pietro Ragni Susana Iglesias-Groth Arturo Manchado 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(2):573-580
The sulphur-containing proteinaceous amino acids l-cysteine, l-cystine and l-methionine were irradiated in the solid state to a dose of 3.2 MGy. This dose corresponds to that delivered by radionuclide
decay in a timescale of 1.05 × 109 years to the organic matter buried at a depth >20 m in comets and asteroids. The purity of the sulphur-containing amino acids
was studied by differential scanning calorimetry (DSC) before and after the solid state radiolysis and the preservation of
the chirality after the radiolysis was studied by chirooptical methods (optical rotatory dispersion, ORD) and by FT-IR spectroscopy.
Although the high radiation dose of 3.2 MGy delivered, all the amino acids studied show a high radiation resistance. The best
radiation resistance was offered by l-cysteine. The radiolysis of l-cysteine leads to the formation of l-cystine. The radiation resistance of l-methionine is not at the level of l-cysteine but also l-methionine is able to survive the dose of 3.2 MGy. Furthermore in all cases examined the preservation of chirality after
radiolysis was clearly observed by the ORD spectroscopy although a certain level of radioracemization was measured in all
cases. The radioracemization is minimal in the case of l-cysteine and is more pronounced in the case of l-methionine. In conclusion, the study shows that the sulphur-containing amino acids can survive for 1.05 × 109 years and, after extrapolation of the data, even to the age of the Solar System i.e. to 4.6 × 109 years. 相似文献