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41.
Scots pine (SO) and clove (CO) essential oils (EOs) are commonly used by inhalation, and their main components are shown to reduce inflammatory mediator production. The aim of our research was to investigate the chemical composition of commercially available SO and CO by gas chromatography–mass spectrometry and study their effects on airway functions and inflammation in an acute pneumonitis mouse model. Inflammation was evoked by intratracheal endotoxin and EOs were inhaled three times during the 24 h experimental period. Respiratory function was analyzed by unrestrained whole-body plethysmography, lung inflammation by semiquantitative histopathological scoring, myeloperoxidase (MPO) activity and cytokine measurements. α-Pinene (39.4%) was the main component in SO, and eugenol (88.6%) in CO. Both SO and CO significantly reduced airway hyperresponsiveness, and prevented peak expiratory flow, tidal volume increases and perivascular edema formation. Meanwhile, inflammatory cell infiltration was not remarkably affected. In contrast, MPO activity and several inflammatory cytokines (IL-1β, KC, MCP-1, MIP-2, TNF-α) were aggravated by both EOs. This is the first evidence that SO and CO inhalation improve airway function, but enhance certain inflammatory parameters. These results suggest that these EOs should be used with caution in cases of inflammation-associated respiratory diseases.  相似文献   
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The photo-induced formation of ketonic and phenolic isomers from O-acetyl-1-dehydro-testosterone ( 1a ) and from its 4-methyl homologue 1d in dioxane solution has been described earlier [8][9][13]. The present paper summarizes the findings which resulted in the course of further investigations, and which, in part, have been published in preliminary form [11][14] and in recent reviews [12]. This work includes the ultraviolet irradiation of dienone 1a , its 10α-stereoisomer 2a , and its 1-, 2- and 4-methyl homologues 1b – d . A series of rearrangements occurred in each case, as shown in Charts 2, 3, and 19.  相似文献   
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Structure of copolymers of p-methyl-p′-acryloyloxy azoxybenzene (MAAB) with cholesterylvinyl succinate (CVS) was studied by small- and wide-angle X-ray diffractometry, DSC, polarizing microscopy, and thermomechanical methods. The copolymers were found to be anisotropic non-crystalline substances in which the radial distribution of the radius of gyration of inhomogeneities corresponds to that of the diameter of the molecules determined by GPC. Both phase transition temperatures and clearing points of copolymers show a minimum as functions of the composition. On both sides of this minimum, the copolymers have different structures. At higher MAAB contents, the copolymer structure is similar to that of polyMAAB; at lower MAAB concentrations, alternating copolymer is formed similar in structure to polyCVS. For identification of the structures, copolymer/comonomer phase diagrams were also investigated.  相似文献   
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Summary The concentration dependent effects of deep rough mutant lipopolysaccharide (LPS) from Salmonella minnesota (R595) on two different phospholipid model membranes was investigated by differential scanning calorimetry and small-angle X-ray scattering (SAXS). At low concentrations of LPS the well ordered multilamellar arrangement of dipalmitoylphosphatidylcholine (DPPC) vesicles is strongly distorted resulting in a loss of positional correlation of the lipid lamellae and smaller domain sizes within the lamellae. The pre-transition of DPPC was abolished at a LPS/DPPC molar ratio of 0.1:1 and the main or chain melting transition was strongly broadened. Moreover, the enthalpy was significantly decreased and a transition was hardly detected at an equimolar mixture of LPS/DPPC. LPS also affected the lamellar arrangement of a mixture of dipalmitoylphosphatidylethanolamine (DPPE) and dipalmitoylphosphatidylglycerol (DPPG). Furthermore, a phase separation was observed for this phospholipid mixture resulting in DPPE enriched and depleted domains. Similarly to DPPC, only a weak phase transition was observed at the highest LPS concentration used (LPS/DPPE-DPPG 1:1 mol/mol). SAXS measurements showed that for both systems increasing the concentration of LPS resulted in a concomitant increase of the formation of cubic structures, which are predominant at an equimolar mixture of LPS/phospholipid. However, because of the small number of peaks it was not possible to unambiguously identify the space group of the cubic structure, complicated by the coexistence with a lamellar phase, which was particularly detectable for the LPS/DPPC mixture.  相似文献   
45.
We established a new reversed phase‐high performance liquid chromatography method combined with electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry for the simultaneous determination and structural characterization of different lipid A types in bacteria (Escherichia coli O111, Salmonella adelaide O35 and Proteus morganii O34) showing serological cross‐reactivity. The complex lipid A mixtures (obtained by simple extraction and acid hydrolysis of the outer membrane lipopolysaccharides) were separated and detected without phosphate derivatization. Several previously unidentified ions were detected, which differed in the number and type of acyl chains and number of phosphate groups. In several cases, we observed the different retention of isobaric lipid A species, which had different secondary fatty acyl distribution at the C2′ or the C3′ sites. The fragmentation of the various, C4′ monophosphorylated lipid A species in deprotonated forms provided structural assignment for each component. Fragmentation pathways of the tri‐acylated, tetra‐acylated, penta‐acylated, hexa‐acylated and hepta‐acylated lipid A components and of the lipid A partial structures are suggested. As standards, the hexa‐acylated ion at m/z 1716 with the E. coli‐type acyl distribution and the hepta‐acylated ion at m/z 1954 with the Salmonella‐type acyl distribution were used. The results confirmed the presence of multiple forms of lipid A in all strains analyzed. In addition, the negative‐ion mode MS permitted efficient detection for non‐phosphorylated lipid A components, too. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
46.
L-Lysine monohydrochloride dihydrate (LLMHCl), a semiorganic potential nonlinear optically active crystal possessing large hyperpolarizability and which belongs to noncentrosymmetry class has been grown and studied. The XRD analysis shows that it belongs to the auspicious symmetric space group P2(1) with two molecules in the asymmetric unit. FTIR and FT Raman of the title crystal have been studied at room temperature. The polarization light and oriented single crystals are used to assign the lines observed in the Raman spectra of the studied material. The vibrational spectral characterization has been carried out and interpreted in the light of crystal structure data and factor group analysis. The second harmonic generation (SHG) measurements have allowed identifying the C2 space group symmetry of the compound corroborating very good propensity for green emission. The optical and mechanical responses have been studied with respect to UV visible and Vickers microhardness measurements.  相似文献   
47.

Synthesis of ammonium hydroxodisulfitoferriate(III), (diammonium catena-{bis(μ 2-sulfito-κO,κO)-μ 2-hydroxo-κ2O}ferrate(III) monohydrate) (NH4)2[Fe(OH)(SO3)2]·H2O (compound 1) and its thermal behavior is reported. The compound is stable in air. Its thermal decomposition proceeds without the expected quasi-intramolecular oxidation of sulfite ion with ferric ions. The disproportionation reaction of the ammonium sulfite, formed from the evolved NH3, SO2 and H2O in the main decomposition stage of 1, results in the formation of ammonium sulfate and ammonium sulfide. The ammonium sulfide is unstable at the decomposition temperature of 1 (150 °C) and transforms into NH3 and H2S which immediately forms elementary sulfur by reaction with SO2. The formation and decomposition of other intermediate compounds like (NH4)2SnOx (n = 2, x = 3 and n = 3, x = 6) results in the same decomposition products (S, SO2 and NH3). Two basic iron sulfates, formed in different ratios during synthesizing experiments performed under N2 or in the presence of air, have been detected as solid intermediates which contain ammonium ions. The final decomposition product was proved to be α-Fe2O3 (mineral name hematite).

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