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1.
Molecularly imprinted polymer (MIP) computational design is expected to become a routine technique prior to synthesis to produce polymers with high affinity and selectivity towards target molecules. Furthermore, using these simulations reduces the cost of optimizing polymerization composition. There are several computational methods used in MIP fabrication and each requires a comprehensive study in order to select a process with results that are most similar to properties exhibited by polymers synthesized through laboratory experiments. Until now, no review has linked computational strategies with experimental results, which are needed to determine the method that is most appropriate for use in designing MIP with high molecular recognition. This review will present an update of the computational approaches started from 2016 until now on quantum mechanics, molecular mechanics and molecular dynamics that have been widely used. It will also discuss the linear correlation between computational results and the polymer performance tests through laboratory experiments to examine to what extent these methods can be relied upon to obtain polymers with high molecular recognition. Based on the literature search, density functional theory (DFT) with various hybrid functions and basis sets is most often used as a theoretical method to provide a shorter MIP manufacturing process as well as good analytical performance as recognition material. 相似文献
2.
Sholpan S. Itkulova Gaukhar D. Zakumbaeva Aliya A. Mukazhanova Yerzan Y. Nurmakanov 《Central European Journal of Chemistry》2014,12(12):1255-1261
The new multicomponent Co-based catalysts with additives of group 8 metal and rare earth elements and supported on alumina have been tested in the dry and steam conversion of a model biogas. The processes were carried out in a flow quartz reactor under the following conditions: atmospheric pressure, a gas hourly space velocity of 1000 h?1 and temperatures of 300–800°C. The catalysts were characterised using electron microscopy, BET and X-ray analysis. The methane is almost completely converted in the dry reforming of biogas at T≤800°C. Synthesis gas with a ratio of H2/CO>1.0 is a main product of biogas reforming over the multicomponent catalysts studied. Adding steam in a feed composition increases both the methane conversion and the hydrogen yield at lower temperatures. Almost complete methane conversion occurs at T<750°C in the steam reforming of biogas. The catalysts are highly effective and exhibit stable activity throughout 100 h of continuous testing. 相似文献
3.
Noworolski SM Tien PC Merriman R Vigneron DB Qayyum A 《Magnetic resonance imaging》2009,27(4):570-576
Purpose
To develop a post-processing, respiratory-motion correction algorithm for magnetic resonance spectroscopy (MRS) of the liver and to determine the incidence and impact of respiratory motion in liver MRS.Materials and Methods
One hundred thirty-two subjects (27 healthy, 31 with nonalcoholic fatty liver disease and 74 HIV-infected with or without hepatitis C) were scanned with free breathing MRS at 1.5 T. Two spectral time series were acquired on an 8-ml single voxel using TR/TE=2500 ms/30 ms and (1) water suppression, 128 acquisitions, and (2) no water suppression, 8 acquisitions. Individual spectra were phased and frequency aligned to correct for intrahepatic motion. Next, water peaks more than 50% different from the median water peak area were identified and removed, and remaining spectra averaged to correct for presumed extrahepatic motion. Total CH2+CH3 lipids to unsuppressed water ratios were compared before and after corrections.Results
Intrahepatic-motion correction increased the signal to noise ratio (S/N) in all cases (median=11-fold). Presumed extrahepatic motion was present in 41% (54/132) of the subjects. Its correction altered the lipids/water magnitude (magnitude change: median=2.6%, maximum=290%, and was >5% in 25% of these subjects). The incidence and effect of respiratory motion on lipids/water magnitude were similar among the three groups.Conclusion
Respiratory-motion correction of free breathing liver MRS greatly increased the S/N and, in a significant number of subjects, changed the lipids/water ratios, relevant for monitoring subjects. 相似文献4.
Rock Porous Structure Characterization: A Critical Assessment of Various State-of-the-Art Techniques
Razavifar Mehdi Mukhametdinova Aliya Nikooee Ehsan Burukhin Alexander Rezaei Amin Cheremisin Alexey Riazi Masoud 《Transport in Porous Media》2021,136(2):431-456
Transport in Porous Media - The porous structure of geomaterials is of utmost importance for various industrial and natural processes. In this study, various conventional porous structure... 相似文献
5.
New N‐(Aryl)‐5‐((quinolin‐8‐yloxy)methyl)‐1,3,4‐oxa/Thiadiazol‐2‐amines and 4‐Aryl‐5‐((quinolin‐8‐yloxy)methyl)‐2H‐1,2,4‐triazole‐3(4H)‐thiones,Synthesis and Characterization 下载免费PDF全文
Aamer Saeed Naeem Abbas Aliya Ibrar Michael Bolte 《Journal of heterocyclic chemistry》2014,51(5):1357-1362
In this study, methyl 2‐(quinolin‐8‐yloxy) acetate ( 2 ) obtained by reaction of 8‐hydroxyquinoline ( 1 ) with methyl chloroacetate was condensed with hydrazine hydrate to afford the carbohydrazide ( 3 ). Thio/semicarbazide derivatives ( 4a , 4b , 4c , 4d , 4e , 4f , 4g ) were obtained by treatment of the 3 with substituted phenyl iso/thioisocyanates. The 4a , 4b , 4c , 4d , 4e , 4f , 4g on acidic and basic intramolecular cyclization led to N‐(aryl)‐5‐((quinolin‐8‐yloxy)methyl)‐1,3,4‐oxa/thiadiazol‐2‐amines ( 5a , 5b , 5c , 5d , 5e , 5f , 5g ) and 4‐aryl‐5‐((quinolin‐8‐yloxy)methyl)‐2H‐1,2,4‐triazole‐3(4H)‐thiones ( 6a , 6b , 6c , 6d , 6e , 6f , 6g ), respectively. All the synthesized compounds were characterized by spectroscopic techniques and elemental analyses. The thiosemicarbazide ( 4c ) was also confirmed by X‐ray crystallography. 相似文献
6.
Guzel Ziyatdinova Aliya Gainetdinova Mikhail Morozov Herman Budnikov Svetlana Grazhulene Arkady Red’kin 《Journal of Solid State Electrochemistry》2012,16(1):127-134
Glassy carbon electrodes (GCE) modified with carbon nanotubes (CNT) have been created for detection of phenolic compounds—one
of the important group of antioxidants in life sciences. The surface of electrode has been characterized by atomic force microscopy.
The presence of CNT leads to an at least 20-fold increase in the surface roughness of the electrode. The CNT layer displays
closely intertwined vermicular structures with high degree of homogeneity at CNT suspension concentration of 0.2–0.5 mg L−1. Synthetic water-soluble antioxidants (hydroquinone, catechol, pyrogallol, and their derivatives) are electrochemically active
on bare GCE and CNT-modified GCE in phosphate buffer solution pH 7.4. Effect of substitutes in molecular structure of phenolic
antioxidants has been evaluated. In several cases, oxidation at CNT-modified GCE occurs at potentials that are less positive
by 100–200 mV in comparison to bare GCE. The electrodes were studied with respect to their capability of phenols voltammetric
sensing. CNT-modified GCE display an enlarged linear range in the calibration graphs and lower detection limits. Voltammetric
method for determination of hydroquinone, catechol, pyrogallol, and their derivatives has been developed. 相似文献
7.
8.
In this article, we examine voluntary oversight programs for nanotechnology in the context of corporate social performance
(CSP) in order to better understand the drivers, barriers, and forms of company participation in such programs. At the theoretical
level, we use the management framework of CSP to understand the voluntary behavior of companies. At the empirical level, we
investigate nanotech industry participation in the Environmental Protection Agency’s Nanoscale Materials Stewardship Program
(NMSP) as an example of CSP, in order to examine the effects of company characteristics on CSP outcomes. The analysis demonstrates
that, on the average, older and larger companies for which nanotech is one of the many business activities demonstrate greater
CSP as judged by company actions, declarations, and self-evaluations. Such companies tended to submit more of the requested
information to the NMSP, including specific information about health and safety, and to claim fewer of the submitted items
as confidential business information. They were also more likely to have on-line statements of generic and nano-specific corporate
social responsibility principles, policies, and achievements. The article suggests a need to encourage smaller and younger
companies to participate in voluntary oversight programs for nanotechnology and presents options for better design of these
programs. 相似文献
9.
Chemoenzymatic synthesis and modification of well-defined macrolactonic sophorolipid (SLML) analogues via a series of successive regioselective de-esterification/transesterification reactions is investigated. Of the lipases screened, Candida antartica lipase- B (Novozyme-435) successfully deacylated the C-6′ acetoxy group of natural and peracylated SLMLs. Subsequent transesterification with acylating agents (esters of fatty acids) was successful only with the C-6′ deacetylated natural SLML providing an avenue to well-defined analogues of varying amphilicity. The macrolactonic motif was essential for enzymatic recognition of the sophorose rings of these complex glycolipids. In the absence of the lactonic motif, the peracylated sophorose rings are not deacylated, rather the carboxyl end of the non-lactonic forms that was preferentially transesterified. All macrolactonic derivatives were characterized by IR, 1H, 13C, 1H-1H and 1H-13C NMR spectroscopy, as well as HRMS where applicable. 相似文献
10.
Grage SL Suleymanova AV Afonin S Wadhwani P Ulrich AS 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2006,183(1):77-86
Dipolar couplings contain information on internuclear distances as well as orientational constraints. To characterize the structure of the antimicrobial peptide gramicidin S when bound to model membranes, two rigid 4-CF3-phenylglycine labels were attached to the cyclic backbone such that they reflect the behavior of the entire peptide. By solid state 19F NMR we measured the homonuclear dipolar couplings of the two trifluoromethyl-groups in oriented membrane samples. Using the CPMG experiment, both the strong couplings within each CF3-group as well as the weak coupling between the two CF3-groups could be detected. An intra-CF3-group dipolar coupling of 86 Hz and a weak inter-group coupling of 20 Hz were obtained by lineshape simulation of the complex dipolar spectrum. It is thus possible to explore the large distance range provided by 19F-labels and to resolve weak dipolar couplings even in the presence of strong intra-CF3 couplings. We applied this approach to distinguish and assign two epimers of the labeled gramicidin S peptide on the basis of their distinct 19F dipolar coupling patterns. 相似文献