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排序方式: 共有249条查询结果,搜索用时 15 毫秒
101.
Mohamed F. M. Abdelkader Mohamed H. Mahmoud Loay A. A. Mohamed A. Abdein Khaled Metwally Shinya Ikeno Samar M. A. Doklega 《Molecules (Basel, Switzerland)》2022,27(12)
In the present study, an experiment was carried out on the postharvest of cucumber fruit during a 14-day shelf life. The aim was to assess the impact of calcium nanoparticles (CaNPs) blended with different concentrations of salicylic acid (SA) on the shelf life of cucumbers during the seasons of 2018 and 2019. The investigation further monitored the influences of CaNPs-SA on some physical properties of cucumber, including the percentage weight loss, color, and fruit firmness. In addition, chemical properties, such as total soluble solids (SSC%), total acidity (TA%), total soluble sugars, and chlorophyll pigmentation of the fruit skin, were assessed during a 14-day shelf lifeCell wall degradation enzymes (CWEAs) such as polygalacturonase (PG), cel-lulase (CEL), xylanase (XYL), and pectinase (PT) were also researched. In addition, the generation rates of H2O2 and O2•− were calculated, as well as the reduction of DPPH. The lipid peroxidation (malondialdehyde, MDA) and cell membrane permeability (IL%) of cell wall composites were also determined. CaNPs-SA at 2 mM suppressed CWEAs, preserved fruit quality, reduced weight loss throughout the shelf-life period, and reduced the percent leakage value. At this concentration, we also found the lowest levels of MDA and the highest levels of DPPH. 相似文献
102.
Generation of Pseudocontact Shifts in Proteins with Lanthanides Using Small “Clickable” Nitrilotriacetic Acid and Iminodiacetic Acid Tags
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Dr. Choy‐Theng Loh Dr. Bim Graham Elwy H. Abdelkader Dr. Kellie L. Tuck Prof. Gottfried Otting 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(13):5084-5092
Pseudocontact shifts (PCS) induced by paramagnetic lanthanide ions provide unique long‐range structural information in nuclear magnetic resonance (NMR) spectra, but the site‐specific attachment of lanthanide tags to proteins remains a challenge. Here we incorporated p‐azido‐phenylalanine (AzF) site‐specifically into the proteins ubiquitin and GB1, and ligated the AzF residue with alkyne derivatives of small nitrilotriacetic acid and iminodiacetic acid tags using the CuI‐catalysed “click” reaction. These tags form lanthanide complexes with no or only a small net charge and produced sizeable PCSs with paramagnetic lanthanide ions in all mutants tested. The PCSs were readily fitted by single magnetic susceptibility anisotropy tensors. Protein precipitation during the click reaction was greatly alleviated by the presence of 150 mM NaCl. 相似文献
103.
104.
Ben Abdelkader S. Ben Cherifa A. Coulet M. V. Khattech I. Rogez J. Jemal M. 《Journal of Thermal Analysis and Calorimetry》2004,77(3):863-871
Pure and well crystallised whitlockite Ca18Mg2H2(PO4)14 has been synthesized by precipitation from the magnesium and calcium nitrates and the diammonic phosphate. The product of
the reaction has been characterized by X-ray diffraction, IR spectroscopy and chemical analysis. Using differential conduction
calorimeters the enthalpies of solution of the whitlockite and of a mixture of the solid reactants - the tricalcium, the trimagnesium
and the dicalcium phosphates - have been measured at 25°C for various concentrations of solid in a 46 wt% nitric acid solution.
A combination of the enthalpies of solution with the enthalpies of formation of the reactants allows us to determine the standard
enthalpy of formation of the whitlockite. The value deduced, -27,93·103kJ mol-1, is compared to the standard enthalpies of formation of the trimagnesium and the tricalcium phosphates.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
105.
K. Serhan M. Taibi J. Aride A. Boukhari J. Darriet G. Le Flem 《Journal of solid state chemistry》1994,110(2)
The structure of Nd3BGe1.08Si0.92O10 has been determined by a single crystal investigation. The orthorhombic cell parameters are a = 9.845(1) Å, b = 7.146(1) Å, and c = 23.382(2) Å. The space group is Pbca (Z = 8). Out of 10,833 measured reflections, 3,099 independent reflections (I > 3σ(I)) have been used in the refinement of the structure. The R factor value is 0.026 (wR = 0.023). The neodymium ions occupy three different sites with eight or nine oxygen bonds in the lattice. The germanium and silicon ions are located in a distorted tetrahedral environment. The boron atom coordination is triangular with a shorter B-O distance of 1.384 Å. 相似文献
106.
107.
Abdelkader Benderrag Mortada Daaou Boumedienne Bounaceur Boumedienne Haddou 《Chemical Papers》2016,70(9):1196-1203
The influence of water pH and cationic surfactant content on the interfacial properties and stability of an Algerian bitumen aqueous emulsion were investigated. While the stability was quantified by both the test-bottle method and size distribution measurements, the interfacial properties of the water-bitumen interface were assessed using interfacial tension measurements. Optical microscopy was also used to visualise the dispersed water droplets in the oil phase. The results showed that addition of the cationic surfactant at a concentration of 25 mmol L?1 in acidic water (pH 2) improves the bitumen emulsion stability and effectively decreases the interfacial tension. 相似文献
108.
Tabti Hadja Alia Medjahed Baghdad Boudinar Mohamed Kadeche Abdelkader Bouchikhi Noria Ramdani Amina Taleb Safia Adjdir Mehdi 《Research on Chemical Intermediates》2022,48(6):2683-2703
Research on Chemical Intermediates - In this study, Mg-Fe(II)-Al-layered double hydroxide with different molar ratios Fe/Al (Mg0.80-Fe0.14-Al0.06-LDHs and Mg0.80-Fe0.20-Al0.00-LDHs) was prepared... 相似文献
109.
Boudahri Malika Bouazza Djamila Adjdir Mehdi Miloudi Hafida Abdelkader Nebatti Tayeb Abdelkader 《Research on Chemical Intermediates》2018,44(10):6105-6117
Research on Chemical Intermediates - This paper deals with the potential use of hybrid magadiite composite as an alternative adsorbent for the removal of copper ions. Na-magadiite was synthesized... 相似文献
110.
Hachama Kamel Khadraoui Abdelkader Zouikri Mohamed Khodja Mohamed Khelifa Abdellah Echiker Khadidja Hammouti Belkheir 《Research on Chemical Intermediates》2016,42(2):987-996
Research on Chemical Intermediates - A new benzoxazin derivative, namely methyl 3-(2-oxo-2H-1,4-benzoxazin-3-yl) propanoate (1,4-MBXP), was synthesized under mild conditions from 2-aminophenols and... 相似文献