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31.
Relationship among glottal area, static supraglottic compression, and laryngeal function studies in unilateral vocal fold paresis and paralysis 总被引:1,自引:0,他引:1
Steven Bielamowicz Ritu Kapoor Jerome Schwartz Sheila V. Stager 《Journal of voice》2004,18(1):138-145
In this study, we evaluated the relationship between laryngeal function measures and glottal gap ratio and normalized measures of supraglottic behaviors in patients with unilateral vocal fold paresis (UVFP). Thirty-one patients were found to have unilateral vocal fold paresis by videoendoscopy and laryngeal electromyography, and 13 controls participated in this study. Patients with UVFP demonstrated significantly larger glottal gap ratios (p = 0.016) than control subjects. The nonparalyzed or contralateral vocal fold was associated with significantly more static false vocal fold compression (p = 0.03) compared with the paralyzed vocal fold or with the controls. Patients with unilateral vocal fold paresis were divided into subgroups: those with normal or abnormal maximum phonation time, flow, or pressure measures. Smaller glottal gap ratios were identified in patients with normal maximum phonation times and flow measures. Greater false vocal fold activity was identified in unilateral vocal fold paresis patients with normal laryngeal function measures than in unilateral vocal fold paresis patients with abnormal measures. These findings suggest that some patients with documented unilateral paresis and glottal incompetence can compensate for vocal fold weakness such that their acoustic and aerodynamic measures are normal. 相似文献
32.
The total (elastic + inelastic) cross sections fore
+ impact on alkaline-earth elements from Be to Ra are calculated by employing a complex spherical optical potential. This potential
has static, polarization and absorption components. The positron energy range is from a few eV to several thousand eV. We
have compared our elastic cross sections for Mg and Ca with the other available results and the agreement is good for energies
above 100eV. We have also compared our absorption cross sections withe
− ionization cross sections at high energies where our absorption cross sections are in good accord. We have made Bethe plots
fore
+ scattering on these elements. 相似文献
33.
Manju K. Saroj Ritu Payal Sapan K. Jain Neera Sharma Ramesh C. Rastogi 《Journal of inclusion phenomena and macrocyclic chemistry》2018,90(3-4):305-320
The study focuses on the formation of inclusion complexes of indole chalcone (IC) derivatives with β-cyclodextrin (β-CD), which involves absorption and steady state fluorescence spectroscopies. The formation of inclusion complexes is validated by increase in their absorbance and fluorescence intensity as well as the blue shift with increase in the concentration of β-CD in the aqueous solution. The stoichiometries and binding constants (Kin) of these complexes have been investigated by monitoring their absorbance and fluorescence spectral profiles. The data are analyzed by Benesi–Hildebrand plots as well as Job’s method, which indicate 1:1 stoichiometry of IC:β-CD complexes. Fluorescence measurements are also used to investigate the effect of temperature on the stability of inclusion complexes. Stability of IC:β-CD complexes is significantly affected with variation in substituents on the phenyl ring and temperature. It is observed that the stability of the inclusion complex decreases with increase in temperature; Kin(293 K)?>?Kin(298 K)?>?Kin(308 K)?>?Kin(318 K). All the experimental results and the geometrical data obtained using PM3 semiempirical method illustrate the partial inclusion of IC derivatives from the phenyl ring side in β-CD cavity. The binding process of IC derivatives with β-CD is found to be exothermic in nature and seems to be controlled by electrostatic and hydrophobic forces. The binding free energies calculated using semiemprical PM3 method for IC:β-CD complexes are found to be in the order: I?<?OH–I?<?Me–I?<?OMe–I?<?NH2–I, which largely supports the findings based on the experimental binding constants. 相似文献
34.
We report an exceptionally mild, general and efficient copper catalyzed cross coupling reaction of aryl bromides and thiols using 0.5 mol % CuI and 1 mol % benzotriazole. Experimental simplicity, generality, functional group tolerance and low cost of the catalyst are advantages of the protocol. 相似文献
35.
Lobana TS Sharma R Sharma R Mehra S Castineiras A Turner P 《Inorganic chemistry》2005,44(6):1914-1921
Reaction of copper(I) iodide with pyridine-2-thione (2-SC5H4NH) and 1,2-bis(diphenylphosphino)ethane (dppe) in a CH3CN-CHCl3 mixture yielded a triangular cluster, [Cu3I3(mu2-P,P-dppe)3 (eta1-SC5H4NH)], 1. Similar reaction with 2-SC5H4NH and a series of diphosphanes, Ph2P-X-Ph2P {X = -CH2- (dppm), -(CH2)3- (dppp), -(CH2)4- (dppb), -CH=CH- (dppen)}, gave a novel iodo-bridged hexanuclear Cu(I) linear polymer,{Cu6(mu3-SC5H4NH)4 (mu2-SC5H4NH)2 (I4)(mu-I)2-}n x 2nCH3CN, 2. Reactions of copper(I) iodide/copper(I) bromide with 1,3-imidazolidine-2-thione (SC3H6N2) in a CH3CN-CHCl3 mixture yielded hexanuclear Cu(I) linear chain polymers, [{Cu6(mu3-SC3H6N2)2 (mu2-SC3H6N2)4X2 (mu-X)4}n] (X = Br, 4; I, 5). In compound 1, two iodide atoms and one dppe form the dinuclear Cu(mu2-I)2 (mu2-dppe)Cu core, and two dppe ligands bridge this core with the third Cu(I) center coordinated to 2-SC5H4NH via the S atom. The chain polymer 2 has a centrosymmetric hexanuclear central core, Cu6S6I4 (mu-I)2--, formed by dimerization of six-membered trinuclear motifs, Cu3(mu2-SC3H6N2)3I3 via (mu3-S) bonding modes of the thione ligand, and has four terminal and two bridging iodine atoms in trans-orientations. Linear chains are separated by the nonbonded acetonitrile molecules. In 4 and 5, three copper(I) bromide or copper(I) iodide moieties and three SC3H6N2 ligands combined via bridging S donor atoms to form the six-membered trinuclear Cu3(mu2-SC3H6N2)3I3 cores which polymerized via S and X atoms in a side-on fashion to form linear chain polymers, [{Cu6(mu3-SC3H6N2)2 (mu2-SC3H6N2)4X2(mu-X)4}n]. The (mu3-S) modes of bonding of neutral heterocyclic thioamides are first examples, as are trinuclear cluster and linear polymers rare examples in copper chemistry. 相似文献
36.
Vikas Mishra Vijaya Lakshmi Nag Ritu Tandon Shally Awasthi 《Applied biochemistry and biotechnology》2010,160(8):2322-2331
Management of rotavirus diarrhoea cases and prevention of nosocomial infection require rapid diagnostic method at the patient
care level. Diagnostic tests currently available are not routinely used due to economic or sensitivity/specificity constraints.
Agarose-based sieving media and running conditions were modulated by using central composite design and response surface methodology
for screening and electropherotyping of rotaviruses. The electrophoretic resolution of rotavirus genome was calculated from
input parameters characterising the gel matrix structure and running conditions. Resolution of rotavirus genome was calculated
by densitometric analysis of the gel. The parameters at critical values were able to resolve 11 segmented rotavirus genome.
Better resolution and electropherotypic variation in 11 segmented double-stranded RNA genome of rotavirus was detected at
1.96% (w/v) agarose concentration, 0.073 mol l−1 ionic strength of Tris base–boric acid–ethylenediamine tetraacetic acid buffer (1.4×) and 4.31 h of electrophoresis at 4.6 V cm−1 electric field strength. Modified agarose gel electrophoresis can replace other methods as a simplified alternative for routine
detection of rotavirus where it is not in practice. 相似文献
37.
Das Ritu Dhiman Abhijeet Kapil Arti Bansal Vipul Sharma Tarun Kumar 《Analytical and bioanalytical chemistry》2019,411(6):1229-1238
Analytical and Bioanalytical Chemistry - Despite of various advancements in biosensing, a rapid, accurate, and on-site detection of a bacterial pathogen is a real challenge due to the lack of... 相似文献
38.
Tarlok Singh Lobana Mani Kaushal Robin Bhatia Ritu Bala Ray J. Butcher Jerry P. Jasinksi 《Acta Crystallographica. Section C, Structural Chemistry》2022,78(1):30-35
In this investigation, the crystal structures of the thio-ligands 3-formylpyridine 4-phenylthiosemicarbazone (C13H12N4S, 1 ) and 4-benzoylpyridine 4-ethylthiosemicarbazone (C15H16N4S, 2 ), and of two new coordination compounds, chlorido(3-formylpyridine 4-phenylthiosemicarbazone-κS)bis(triphenylphosphane-κP)copper(I) acetonitrile monosolvate, [CuCl(C13H12N4S)(C18H15P)2]·CH3CN, 3 , and bis(3-formylpyridine 4-ethylthiosemicarbazonato-κ2N1,S)nickel(II), [Ni(C9H11N4S)2], 4 , are reported. In complex 3 , the thio-ligand coordinates in a neutral form to the Cu atom through its S-donor atom, and in complex 4 , the anionic thio-ligand chelates to the Ni atom through N- and S-donor atoms. The geometry of complex 3 is distorted tetrahedral [bond angles 99.70 (5)–123.23 (5)°], with the P—Cu—P bond angle being the largest, while that of complex 4 is square planar, with trans-S—Ni—S and N—Ni—N bond angles of 180°. 相似文献
39.
Mazaahir?KidwaiEmail author Poonam?Mothsra Vikas?Bansal Ritu?Goyal 《Monatshefte für Chemie / Chemical Monthly》2006,137(9):1189-1194
Summary. Elemental iodine is used as an efficient catalyst for the synthesis of 2,4,5-triarylimidazoles in excellent yields via condensation of benzoin, ammonium acetate, and aromatic aldehydes. This is a simple, one-pot, high yielding technique using
cheap, non-toxic iodine in catalytic amounts. 相似文献
40.
Mazaahir Kidwai Poonam Mothsra Vikas Bansal Ritu Goyal 《Monatshefte für Chemie / Chemical Monthly》2006,120(5):1189-1194
Elemental iodine is used as an efficient catalyst for the synthesis of 2,4,5-triarylimidazoles in excellent yields via condensation of benzoin, ammonium acetate, and aromatic aldehydes. This is a simple, one-pot, high yielding technique using
cheap, non-toxic iodine in catalytic amounts. 相似文献