全文获取类型
收费全文 | 116篇 |
免费 | 2篇 |
专业分类
化学 | 88篇 |
晶体学 | 2篇 |
数学 | 2篇 |
物理学 | 26篇 |
出版年
2022年 | 7篇 |
2021年 | 6篇 |
2020年 | 8篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 1篇 |
2015年 | 4篇 |
2014年 | 4篇 |
2013年 | 7篇 |
2012年 | 5篇 |
2011年 | 3篇 |
2010年 | 3篇 |
2009年 | 4篇 |
2008年 | 5篇 |
2007年 | 5篇 |
2006年 | 14篇 |
2005年 | 6篇 |
2004年 | 1篇 |
2003年 | 5篇 |
2002年 | 4篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 5篇 |
1993年 | 1篇 |
1992年 | 4篇 |
1979年 | 1篇 |
排序方式: 共有118条查询结果,搜索用时 15 毫秒
1.
2.
3.
L. C. Machado A. A. L. Marins E. J. B. Muri J. A. S. Lacerda V. O. Balthar P. F. Fulvio J. C. C. Freitas 《Journal of Thermal Analysis and Calorimetry》2004,75(2):615-621
This paper presents the reactions of synthesis between the ligand sodium diphenylamine-4-sulfonate and the lanthanum(III)
chloride hydrated. The compounds (LaCl3)2·(C12H10NSO3Na)3·2(CH3CH2OH) (A) and (LaCl3)·(C12H10NSO3Na)·(CH3CH2OH)·12H2O (B) were obtained using the solvents ethanol and methanol (synthesis A) and ethanol and water (synthesis B). The produced
compounds and the ligand were characterized by thermogravimetric and differential thermogravimetric analysis, IR spectroscopy
and elemental analysis of sodium, carbon, hydrogen, nitrogen, sulfur, chlorine and lanthanum, whereas the residues from thermal
decomposition were investigated by X-ray diffractometry.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
4.
Dr. Saida Majdoub Dr. Zoltán Garda Alexandre C. Oliveira Dr. Inga Relich Agnès Pallier Dr. Sara Lacerda Dr. Christelle Hureau Dr. Carlos F. G. C. Geraldes Dr. Jean-François Morfin Dr. Éva Tóth 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(6):2009-2020
Metal chelates targeted to amyloid peptides are widely explored as diagnostic tools or therapeutic agents. The attachment of a metal complex to amyloid recognition units typically leads to a decrease in peptide affinity. We show here that by separating a macrocyclic GdL chelate and a PiB targeting unit with a long hydrophobic C10 linker, it is possible to attain nanomolar affinities for both Aβ1-40 (Kd=4.4 nm ) and amylin (Kd=4.5 nm ), implicated, respectively in Alzheimer's disease and diabetes. The Scatchard analysis of surface plasmon resonance data obtained for a series of amphiphilic, PiB derivative GdL complexes indicate that their Aβ1-40 or amylin binding affinity varies with their concentration, thus micellar aggregation state. The GdL chelates also affect peptide aggregation kinetics, as probed by thioflavin-T fluorescence assays. A 2D NMR study allowed identifying that the hydrophilic region of Aβ1-40 is involved in the interaction between the monomer peptide and the Gd3+ complex. Finally, ex vivo biodistribution experiments were conducted in healthy mice by using 111In labeled analogues. Their pancreatic uptake, ∼3 %ID g−1, is promising to envisage amylin imaging in diabetic animals. 相似文献
5.
Cleoci Beninca Tiago André Denck Colman Luiz Gustavo Lacerda Marco Aurélio da Silva Carvalho Filho Ivo Mottin Demiate Gilbert Bannach Egon Schnitzler 《Journal of Thermal Analysis and Calorimetry》2013,111(3):2217-2222
The use of chemically modified starches is widely accepted in various industries, with several applications. In this research, natural cassava starch granules were treated with standard sodium hypochlorite solution at 0.8, 2.0, and 5.0 g Cl/100 g starch. The native and modified starch samples were investigated by means of the following techniques: simultaneous thermogravimetry–differential thermal analysis, which allowed us to verify the thermal decomposition associated with endothermic or exothermic phenomena; and differential scanning calorimetry that was used to determine gelatinization enthalpy as well as the rapid viscoamylographic analysis that provided the pasting temperature and viscosity. By means of non-contact-atomic force microscopy method and X-ray powder patterns diffractometry, it was possible to observe the surface morphology, topography of starch granules, and alterations in the granules’ crystallinity. 相似文献
6.
Ana Luiza Coeli Cruz Ramos Laiza Andrade Nogueira Mauro Ramalho Silva Ana Carolina do Carmo Mazzinghy Ana Paula Xavier Mariano Tssia Nunes de Albuquerque Rodrigues Ana Cardoso Clemente Filha Ferreira de Paula Angelita Cristine de Melo Rodinei Augusti Raquel Linhares Bello de Araújo Inayara Cristina Alves Lacerda Júlio Onsio Ferreira Melo 《Molecules (Basel, Switzerland)》2022,27(15)
Grumixama (Eugenia brasiliensis Lam.) is a native fruit of the Brazilian Atlantic Forest, belonging to the Myrtaceae family, which designatesthe most significant number of species with food potential. It stands out due to its phytochemical characteristics because of the presence of polyphenols and volatile organic compounds. Volatile compounds are substances released by foods that give off an aroma and influence flavor. Solid-phase microextraction is a technique that allows for low-cost, fast, and solvent-free extraction, has an affinity for numerous analytes, and is easily coupled to gas chromatography. The objectives of this work were to evaluate the efficiency of different fibers of SPME (solid-phase microextraction) in the extraction of volatile organic compounds from grumixama pulp; optimize a method for extraction time, temperature, and sample weight; and to determine the characteristic volatile profile of this fruit. For the extraction of volatile compounds, three fibers of different polarities were used: polar polyacrylate (PA) fibers, divinylbenzene/carboxyne/polydimethylsiloxane (DVB/CAR/PDMS) semipolar fibers, and polydimethylsiloxane/divinylbenzene (PDMS/DVB). Fourteen volatile organic compounds (VOCs) were identified by DVB/CAR/PDMS, six by PA, and seven by PDMS/DVB through solid-phase microextraction in the headspace mode (SPME-HS). Considering the total number of compounds identified, regardless of the fiber used, and the optimization of the method, Eugenia brasiliensis presented sesquiterpene fractions (85.7%, 83.3%, and 85.7% of total VOCs) higher than the monoterpene fractions (14.3%, 16.7%, and 14.3%) for DVB/CAR/PDMS, PA, and PDMS/DVB, respectively in its composition. In addition, it was possible to verify that the fiber DVB/CAR/PDMS presented a better efficiency due to the larger chromatographic area observed when the grumixama pulp was subjected to conditions of 75 °C, 2.0 g, and an adsorption time of 20 min. 相似文献
7.
Rodolfo G. Fiorot João F. Allochio Filho Thieres M.C. Pereira Valdemar Lacerda Jr. Reginaldo B. dos Santos Wanderson Romão Sandro J. Greco 《Tetrahedron letters》2014
A clean, efficient and facile one-pot protocol was developed for the synthesis of a series of new aminonaphthoquinones derived from 2-hydroxy-1,4-naphthoquinone (lawsone) by three-component Mannich reaction using catalytic amount of p-TsOH in CH3CN, at room temperature. At the present work, we improved the yield and significantly reduced the reaction time for several Mannich reactions with different amine and aromatic aldehydes using a non-expensive, mild catalyst and suitable solvent. 相似文献
8.
Daouda Ndiaye Maryame Sy Agns Pallier Sandra Même Isidro de Silva Sara Lacerda Aline M. Nonat Loïc J. Charbonnire va Tth 《Angewandte Chemie (International ed. in English)》2020,59(29):11958-11963
The search for more biocompatible alternatives to Gd3+‐based MRI agents, and the interest in 52Mn for PET imaging call for ligands that form inert Mn2+ chelates. Given the labile nature of Mn2+, high inertness is challenging to achieve. The strongly preorganized structure of the 2,4‐pyridyl‐disubstituted bispidol ligand L1 endows its Mn2+ complex with exceptional kinetic inertness. Indeed, MnL1 did not show any dissociation for 140 days in the presence of 50 equiv. of Zn2+ (37 °C, pH 6), while recently reported potential MRI agents MnPyC3A and MnPC2A‐EA have dissociation half‐lives of 0.285 h and 54.4 h under similar conditions. In addition, the relaxivity of MnL1 (4.28 mm ?1 s?1 at 25 °C, 20 MHz) is remarkable for a monohydrated, small Mn2+ chelate. In vivo MRI experiments in mice and determination of the tissue Mn content evidence rapid renal clearance of MnL1. Additionally, L1 could be radiolabeled with 52Mn and the complex revealed good stability in biological media. 相似文献
9.
Gatto Claudia C. Chagas Marcio A. S. Lima Iariane J. Mello Andrade Francyelli Silva Hugo D. Abrantes Gabrielly R. Lacerda Elisângela P. S. 《Transition Metal Chemistry》2019,44(4):329-340
Transition Metal Chemistry - The present study reports the synthesis and crystal structures of Cu(II) complexes with pyridoxal S-allyldithiocarbazate (H2L1) and pyridoxal thiosemicarbazones... 相似文献
10.
Llobet A Christianson AD Bao W Gardner JS Swainson IP Lynn JW Mignot JM Prokes K Pagliuso PG Moreno NO Sarrao JL Thompson JD Lacerda AH 《Physical review letters》2005,95(21):217002
The heavy fermion system exhibits properties that range from an incommensurate antiferromagnet for small to an exotic superconductor on the Ir-rich end of the phase diagram. At intermediate where antiferromagnetism coexists with superconductivity, two types of magnetic order are observed: the incommensurate one of and a new, commensurate antiferromagnetism that orders separately. The coexistence of -electron superconductivity with two distinct -electron magnetic orders is unique among unconventional superconductors, adding a new variety to the usual coexistence found in magnetic superconductors. 相似文献