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321.
The modern technologies use many multilayer composites comprising, the connection of different classes substrates: ceramics, metals, polymers, etc. In this work we focused our attention on an application of confocal micro-Raman spectroscopy to study the multilayer composites. Different multilayer model systems were used to check the role of the confocal mode. The problem of the transparency of layer, and their thickness were discussed. The procedure of determination of interfaces from so-called depth profiles and their first derivatives was also presented. 相似文献
322.
Eberhard Matern Jolanta Olkowska‐Oetzel Jerzy Pikies Gerhard Fritz 《无机化学与普通化学杂志》2001,627(8):1767-1770
The Reactions of tBu2P–P=P(Me)tBu2 and (Me3Si)tBuP–P=P(Me)tBu2 with PR3 tBu2P–P=P(Me)tBu2 ( 1 ) reacts at 20 °C with PMe3, PEt3, P(c‐Hex)3, P(p‐Tol)3, PPh2Me, PPh2Et, PPhEt2, PPh2iPr, PPh3 and P(NEt2)3 yielding tBu2P–P=PR3 and tBu2PMe; however, PtBu3, PtBu2(SiMe3) and tBu2PCl don't. tBu2PH and 1 form tBu2P–PH–PtBu2 which yields tBu2P–P=PEt3 when treated with PEt3. Ph2PH, tBuPH2, PH3, Ph2PCl and EtOH don't substitute the tBu2PMe group in 1 , instead, the molecule is decomposed. With PEt3, (Me3Si)tBuP–P=P(Me)tBu2 forms (Me3Si)tBuP–P=PEt3. The compounds tBu2P–P=PR3 decompose at 20 °C to different degrees giving P‐rich consecutive products of the phosphinophosphinidene. 相似文献
323.
Harald Krautscheid Eberhard Matern Jolanta Olkowska‐Oetzel Jerzy Pikies Gerhard Fritz 《无机化学与普通化学杂志》2001,627(7):1505-1507
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XXIV. Formation and Structure of [μ‐(1,2 : 2‐η‐tBu2P–P){Mo(CO)2cp′}2] [cp′Mo(CO)2]2 (cp′ = C5H4tBu) reacts with tBu2P–P=P(Me)tBu2 to yield the compound [μ‐(1,2 : 2‐η‐tBu2P–P){Mo(CO)2cp′}2], which crystallizes in the space group P212121 with a = 1202.42(7), b = 1552.48(8), and c = 1765.3(1) pm. 相似文献
324.
Jacek Baj Wojciech Flieger Dominika Przygodzka Grzegorz Buszewicz Grzegorz Teresiski Magdalena Pizo Ryszard Maciejewski Jolanta Flieger 《Molecules (Basel, Switzerland)》2022,27(3)
The routine techniques currently applied for the determination of nicotine and its major metabolites, cotinine, and trans-3′-hydroxycotinine, in biological fluids, include spectrophotometric, immunoassays, and chromatographic techniques. The aim of this study was to develop, and compare two new chromatographic methods high-performance liquid chromatography coupled to triple quadrupole mass spectrometry (HPLC-QQQ-MS/MS), and RP-HPLC enriched with chaotropic additives, which would allow reliable confirmation of tobacco smoke exposure in toxicological and epidemiological studies. The concentrations of analytes were determined in human plasma as the sample matrix. The methods were compared in terms of the linearity, accuracy, repeatability, detection and quantification limits (LOD and LOQ), and recovery. The obtained validation parameters met the ICH requirements for both proposed procedures. However, the limits of detection (LOD) were much better for HPLC-QQQ-MS/MS (0.07 ng mL−1 for trans-3′-hydroxcotinine; 0.02 ng mL−1 for cotinine; 0.04 ng mL−1 for nicotine) in comparison to the RP-HPLC-DAD enriched with chaotropic additives (1.47 ng mL−1 for trans-3′-hydroxcotinine; 1.59 ng mL−1 for cotinine; 1.50 ng mL−1 for nicotine). The extraction efficiency (%) was concentration-dependent and ranged between 96.66% and 99.39% for RP-HPLC-DAD and 76.8% to 96.4% for HPLC-QQQ-MS/MS. The usefulness of the elaborated analytical methods was checked on the example of the analysis of a blood sample taken from a tobacco smoker. The nicotine, cotinine, and trans-3′-hydroxycotinine contents in the smoker’s plasma quantified by the RP-HPLC-DAD method differed from the values measured by the HPLC-QQQ-MS/MS. However, the relative errors of measurements were smaller than 10% (6.80%, 6.72%, 2.04% respectively). 相似文献
325.
Ingo Krossing Ulli Englert Eberhard Matern Jolanta Olkowska‐Oetzel Jerzy Pikies Gerhard Fritz 《无机化学与普通化学杂志》2002,628(2):446-452
tBu2P‐P=P(Me)tBu2 reacts with [Fe2(CO)9] to give [μ‐(1, 2, 3:4‐η‐tBu2P1‐P2‐P3‐P4tBu2){Fe(CO)3}{Fe(CO)4}] ( 1 ) and [trans‐(tBu2MeP)2Fe(CO)3]( 2 ). With [(η2‐C8H14)2Fe(CO)3] in addition to [μ‐(1, 2, 3:4‐η‐tBu2P1‐P2‐P3‐P4tBu2){Fe(CO)2PMetBu2}‐{Fe(CO)4}] ( 10 ) and 2 also [(μ‐PtBu2){μ‐P‐Fe(CO)3‐PMetBu2}‐{Fe(CO)3}2(Fe‐Fe)]( 9 ) is formed. 1 crystallizes in the monoclinic space group P21/c with a = 875.0(2), b = 1073.2(2), c = 3162.6(6) pm and β = 94.64(3)?. 2 crystallizes in the monoclinic space group P21/c with a = 1643.4(7), b = 1240.29(6), c = 2667.0(5) pm and β = 97.42(2)?. 9 crystallizes in the monoclinic space group P21/n with a = 1407.5(5), b = 1649.7(5), c = 1557.9(16) pm and β = 112.87(2)?. 相似文献
326.
Karolina Woziwodzka Jolanta Mayszko Ewa Koc-rawska Marcin rawski Paulina Dumnicka Artur Jurczyszyn Krzysztof Batko Paulina Mazur Magorzata Banaszkiewicz Marcin Krzanowski Paulina Goasa Jacek A. Mayszko Ryszard Drod Katarzyna Krzanowska 《Molecules (Basel, Switzerland)》2022,27(1)
Transgelin is a 22-kDa protein involved in cytoskeletal organization and expressed in smooth muscle tissue. According to animal studies, it is a potential mediator of kidney injury and fibrosis, and moreover, its role in tumorigenesis is emerging in a variety of cancers. The study included 126 ambulatory patients with multiple myeloma (MM). Serum transgelin-2 concentrations were measured by enzyme-linked immunoassay. We evaluated associations between baseline transgelin and kidney function (serum creatinine, estimated glomerular filtration rate—eGFR, urinary markers of tubular injury: cystatin-C, neutrophil gelatinase associated lipocalin—NGAL monomer, cell cycle arrest biomarkers IGFBP-7 and TIMP-2) and markers of MM burden. Baseline serum transgelin was also evaluated as a predictor of kidney function after a follow-up of 27 months from the start of the study. Significant correlations were detected between serum transgelin-2 and serum creatinine (R = 0.29; p = 0.001) and eGFR (R = −0.25; p = 0.007). Transgelin significantly correlated with serum free light chains lambda (R = 0.18; p = 0.047) and serum periostin (R = −0.22; p = 0.013), after exclusion of smoldering MM patients. Patients with decreasing eGFR had higher transgelin levels (median 106.6 versus 83.9 ng/mL), although the difference was marginally significant (p = 0.05). However, baseline transgelin positively correlated with serum creatinine after the follow-up period (R = 0.37; p < 0.001) and negatively correlated with eGFR after the follow-up period (R = −0.33; p < 0.001). Moreover, higher baseline serum transgelin (beta = −0.11 ± 0.05; p = 0.032) significantly predicted lower eGFR values after the follow-up period, irrespective of baseline eGFR and follow-up duration. Our study shows for the first time that elevated serum transgelin is negatively associated with glomerular filtration in MM and predicts a decline in renal function over long-term follow-up. 相似文献
327.
Jolanta Maliska‐Solich 《Macromolecular bioscience》2001,1(7):312-321
The condensation and polycondensations of terephthaldehyde ( 1 ) and methyl D ‐hexopyranosides (gluco‐, galacto‐ and mannopyranoside) are described. Methyl α‐D ‐glucopyranoside and methyl α‐D ‐galactopyranoside react with 1 to give mono‐ 5 a and 6 a and diacetals 5 b and 6 b . Their structures were confirmed by NMR and IR spectroscopy. The polycondensation of methyl α‐D ‐mannopyranoside ( 4 ) with 1 was studied in various solvents within the temperature range of 80–140°C. Regardless of the conversion or the initial comonomer feed ratios the composition of polycondensates depended on the reaction conditions leading to the formation of materials with diverse solubilities, molecular weights and optical properties. The regioselective polycondensation of 1 and 4 was examined by the 1H NMR spectroscopy of polymer 7 . In the case of five‐membered cyclic acetal units, mixtures of the endo‐H and exo‐H dioxolan‐2‐yl system diastereomers are formed. Experimental examples of functionalization via ester units in polymer molecules 8 are described and the efficiency of the reaction routes and procedures are evaluated. The molecular weight was estimated by size‐exclusion chromatography (SEC) measurements before and after the functionalization. 相似文献
328.
Vilija Kederien Indr Jaglinskait Paulina Voznikait Jolanta Rousseau Patrick Rollin Algirdas a
kus Arnaud Tatibouët 《Molecules (Basel, Switzerland)》2021,26(22)
Cu-catalyzed N-arylation is a useful tool for the chemical modification of aromatic heterocycles. Herein, an efficient carbon–nitrogen cross-coupling of methyl 3-amino-1-benzothiophene-2-carboxylate with a range of (hetero)aryl iodides using CuI, l-proline and Cs2CO3 in dioxane at moderate temperature is described. The procedure is an extremely general, relatively cheap, and experimentally simple way to afford the N-substituted products in moderate to high yields. The structures of the new heterocyclic compounds were confirmed by NMR spectroscopy and HRMS investigation. 相似文献
329.
330.
This study demonstrates pattern generation on a highly durable and flat diamond-like-carbon (DLC) film with micro/nano-scale resolution using the Atomic Force Microscope (AFM). Parallel processing (masked lithography) and serial local probe processing (maskless lithography) have both been utilized to produce a range of structure shapes at different length scales. The AFM is operated in the electrical conductivity mode which induces oxidation on the DLC surface. The technique offers features with structure depths as small as 20 nm (serial processing) and pattern replication of many centimeters (parallel processing). Moreover parallel processed structures may be further modified via serial patterning using the same instrumentation. As a result, complex shapes can be produced with a depth being controlled by the DLC film thickness and/or by the bias voltage parameters. The patterned DLC structures can be used as a template for fabrication of 3 dimensional polymeric structures. 相似文献