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排序方式: 共有155条查询结果,搜索用时 31 毫秒
1.
Frontispiece: New Dual Fluorescent Probe for Simultaneous Biothiol and Phosphate Bioimaging 下载免费PDF全文
2.
Tomasz Ligor Joanna Zawadzka Grzegorz Strczyski Rosa M. Gonzlez Paredes Anna Wenda-Piesik Ileana Andreea Ratiu Marek Muszytowski 《Molecules (Basel, Switzerland)》2021,26(7)
Volatile organic compounds (VOCs) exiting in urine are potential biomarkers of chronic kidney diseases. Headspace solid phase microextraction (HS-SPME) was applied for extraction VOCs over the urine samples. Volatile metabolites were separated and identified by means of two-dimensional gas chromatography and time of flight mass spectrometry (GC × GC TOF MS). Patients with glomerular diseases (n = 27) and healthy controls (n = 20) were recruited in the study. Different VOCs profiles were obtained from patients and control. Developed methodology offers the opportunity to examine the metabolic profile associated with glomerulopathy. Four compounds found in elevated amounts in the patients group, i.e., methyl hexadecanoate; 9-hexadecen-1-ol; 6,10-dimethyl-5,9-undecadien-2-one and 2-pentanone were proposed as markers of glomerular diseases. 相似文献
3.
A numerical investigation was conducted to analyze the unsteady laminar flow field and heat transfer characteristics in a
plane channel with two square bars mounted side by side to the approaching flow. A finite volume technique is applied with
a fine grid and time resolution. The transverse separation distance between the bars (G/d) is varied from 0 to 5, whereas
the bar height to channel height is d/H=1/8, and the channel length is L=5H. Different flow regimes develop in the channel
due the interaction between the two mounted square bars, steady flow, flow with vortex shedding synchronization either in
phase or in anti-phase, or biased flow with low frequency modulation of vortex shedding are found. Results show that the pressure
drop increase and heat transfer enhancement are strongly dependent of the transverse separation distance of the bars and the
channel Reynolds number. 相似文献
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Conjugated addition of alcohols to 9-hydroxy-and 9-methoxy-1, 4-anthraquinone, in the presence of a strong acid and an oxidant, affords the 2-alkoxy- and 3-alkoxy-substituted regioisomer, respectively. 相似文献
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Mauricio H. Cornejo Jan Elsen Cecilia Paredes Haci Baykara 《Journal of Thermal Analysis and Calorimetry》2014,115(1):309-321
Two Ecuadorian zeolite-rich tuffs, coded as Zeo1 (Mordenite) and Zeo2 (Clinoptilolite–Heulandite–Mordenite), were treated and used as supplementary cementitious materials (SCM) so as to study the effect of the thermal and mechanical treatments on pozzolanic reaction in mortars. The treatment was carried out by means of thermomechanical process according to a central composite-blocked cube-star experimental design. In this experimental design as independent factors the milling time (48, 60, 90, 120 and 132 min) and the heating temperatures (559, 600, 700, 800 and 841 °C) were used but keeping a constant heating time (5 h), and zeolite-rich tuffs as experimental blocks. The proportion of SCM was kept constant i.e. 15 %. On the other hand, the compressive strength, fixed lime, normalized water in hydrates and mg Ca(OH)2 per mg Cement at 7, 28 and 45 days, as well as hydration products related to dehydration degree of the zeolitic tuffs (DOD) were used as dependent factors. In addition, Quantitative and High-temperature chamber XRD, TG-DSC, particle size distribution and SEM-EDS were also carried out. The most significant factor was calcination leading to increase in the compressive strength compared to control, but just up to 800 °C because of recrystallization. As a conclusion, a meaningful loss of crystal structure of zeolites was not observed; but instead, the treatment could only lead to removing the water in cages and voids, thus improving the reaction with Ca(OH)2, producing more hydrates. In addition, lime was not only fixed by pozzolanic reaction, but also by carbonation. 相似文献
9.
Mayté Paredes Zaldivar Norma Galego Fernández Cristina Gastón Peña Manuel Rapado Paneque Sonia Altanés Valentín 《Journal of Thermal Analysis and Calorimetry》2011,106(3):725-730
A new polyacrylic acid/polyhydroxybutyrate semi-interpenetrating polymer network hydrogel, the s-IPN/PAA-PHB, was prepared
by a gamma radiation-induced polymerization. Thermal behavior was studied by thermogravimetric analysis (TG) and Differential
scanning calorimetry (DSC), while the s-IPNs composition, FTIR spectra, and swelling kinetics were also determined. It was
found that the DSC curve showed a melting point which is attributed to polyhydroxybutyrate. The TG curves showed various stages
of degradation which are in correspondence of the presence of crosslinked polyacrylic acid and confirmed the higher thermal
stability of the polymer network. The s-IPN/PAA-PHB composition was 10% of PHB and 90% of PAA. Moreover, the network reached
approximately 600% of swelling in water, so it behaves like a superabsorbent hydrogel. 相似文献
10.
Vernica Paredes‐García Diego Venegas‐Yazigi Alan J. Lough Ramn Latorre 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):e283-e283
We are very interested in characterizing ligands derived from salicylaldehyde and α‐amino acids. These ligands form interesting complexes with different transition metals, which are very useful for understanding some biological systems. For Schiff bases derived from salicylaldehyde and different alkylamines or arylamines, the enol–imine form is predominant. The title compound, (I), shows bond distances which are clearly in agreement with the keto–amine form. 相似文献