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Zeolite Synthesis under Insertion of Silica Rich Filtration Residues from Industrial Wastewater Reconditioning

Advances in chemical Engineering and Science 2014年第2期4卷 120-134页

作者： Andrea Hartmann V.Petrov j.-c.buhl K.Rübner M.Lindemann c.Prinz A.Zimathies Institut für Mineralogie Universitat HannoverHannoverGermany Fachgruppe VII.1 Baustoffe Bundesanstalt für Materialforschung und-prüfung(BAM)BerlinGermany Fachbereich 1.3 Strukturanalytik Richard-Willstätter Bundesanstalt für Materialforschung und-prüfung(BAM)BerlinGermany

Zeolite synthesis was studied using two silica rich filtration residues (FR 1 and FR 2) as Si-source and sodium aluminate in a direct synthesis at 60°c at strong alkaline conditions (8 M - 16 M NaOH). In addition to these one-pot syntheses, a two-step process was investigated. Here, an alkaline digestion of FR at 60°c was followed by gel precipitation with sodium aluminate and gel crystallization under usual conditions of 80°c - 90°c. The results show that the substitution of chemical reagent sodium silicate by a waste material like FR as Si-source is possible but requires fine tuning of the reaction conditions as zeolite crystallization is a process under kinetic control. The solubility behaviour and impurities of the inserted filtration residues strongly influenced the course of reaction. Thus zeolites like hydrosodalite or intermediate zeolite between cancrinite and sodalite, or zeolite NaA or Z-21 in cocrystallization with hydrosodalite could be observed in the one pot syntheses already in a short time interval between 1 - 4 h depending on the alkalinity. The two step process yield to zeolites NaA and NaX in very good quality. The reaction process of FR in both reaction methods was characterized by chemical analyses, X-ray powder diffraction, Fourier transform infrared spectroscopy as well as scanning electron microscopy. Surface area and water content of selected products were further characterized by the BET-method and by thermogravimetry. Summing up the results, we can show that zeolite formation from filtration residues is possible by several reaction procedures as model cases for a re-use of industrial waste materials. Beside the importance for environmental protection, the reactions are of interest for zeolite chemistry as the re-use of FR is possible under economically conditions of low energy consumption at 60°c and short reaction periods.

关键词： Zeolites Superalkaline conditions Filtration Residues Re-Use of Industrial Waste Reaction Kinetics Silica Residue

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The Reality of Baryonic Acoustic Oscillations

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j.urnal of Modern Physics 2024年第3期15卷 377-402页

作者： j. c. Botke Ronin Institute Montclair New Jersey USA

The initial idea for baryonic acoustic oscillations (BAO) came about during early efforts to understand the origin of galaxies by studying perturbed versions of the Friedmann-Robertson-Walker (FRW) model. In more recent times, the emphasis has shifted to the idea that 2-point galaxy correlations embedded in the distribution of matter by the BAO could be used as a standard ruler to fix the parameters of cosmological models. In this paper, we first consider the actual business of extracting the correlation length from large data sets of measured galaxy locations. To facilitate this process, we introduce a much-improved method for extracting the correlation peak from the data set. Fundamental to this process in any model is the use of a fiducial cosmological model to transition from redshift space to comoving coordinate space where the correlations actually exist. The belief is that the correlation length so determined can then be reverted to redshift space to fix the parameters of cosmological models. We show, however, that this process is circular and hence of no value whatsoever for fixing model parameters. All one obtains are the parameters of the model used to transition to comoving space in the first place. Finally, we present simple arguments that show that the idea of BAO being responsible for the structure of the universe, i.e. the cosmic web, is unworkable.

关键词： Baryonic Acoustic Oscillations Two-Point correlations cMB Anisotropy Early Universe Time-Varying curvature

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The Origin of cosmic Structures Part 6: cMB Anisotropy

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j.urnal of High Energy Physics, Gravitation and cosmology 2024年第1期10卷 257-276页

作者： j. c. Botke Ronin Institute Montclair New Jersey USA

In a recent series of papers, we introduced a new model of nucleosynthesis in which the matter content of the universe came into existence at a time of about 4 × 10-5 s. At that time, a small percentage of the vacuum energy was converted into neutron/antineutron pairs with a very small excess of neutrons. This process was regulated by an imprint that was established in the vacuum during an initial Plank-era inflation. Immediately after their inception, annihilation and charge exchange reactions proceeded at a very high rate and ran to completion after an interval of about 10-11 s. By then, all the antibaryons had disappeared thereby establishing the matter/antimatter asymmetry of the universe. What remained were very high densities of mesons and leptons, somewhat lower densities of protons and neutrons, and finally, the very high density of photons that eventually became the cMB. The density of matter so created varied from one location to another in such a manner as to account for all cosmic structures and because the energy density of the photons varied in proportion to that of the matter, the cMB-to-be came into existence with an anisotropic spectrum already in place. For structures, the size of galaxy clusters, the initial anisotropy magnitudes were on the order of 25%. In this paper, we will follow the subsequent evolution of the photons and show that this model predicts with accuracy the temperature of the warmest anisotropies in the observed cMB spectrum. .

关键词： cMB Anisotropy Dispersion Nucleosynthesis Early Universe Time-Varying curvature

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Editorial for the Special Issue on Emerging Technology and Advanced Application of Nondestructive Detection for Power Equipment

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chinese j.urnal of Electrical Engineering 2024年第1期10卷 1-2页

作者： Li j. Mei H. Li S. Tianj.n University China Tsinghua Shenzhen International Graduate School China Lanzhou j.aotong University China

The rapid development of clean and renewable energy technologies represented by wind and solar energy,as well as the continuous growth of load demand,have put forward higher requirements for the safe operation of the power *** performance of power equipment based on traditional dielectric materials is often limited by various defects generated during molding,transportation,assembly,and operation,which cannot meet the reliability requirements of power systems in the new *** detection is an essential technical method in industrial development,which can detect and evaluate the defect and damage status of in-service equipment,key components,and materials without damaging the obj.ct.

关键词： service Application operation

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consumer transparency in the production chain for plant varieties produced using new genomic techniques

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aBIOTEcH 2024年第2期5卷 239-246页

作者： j.M.Lukasiewicz c.c.M.van de Wiel L.A.P.Lotz M.j.M.Smulders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic techniques(NGTs)currently fall under the Genetically Modified Organisms Directive(2001/18/Ec)in the European *** the proposal of the European commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater acceptance of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques consumer transparency Plant products

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Semi-analytical investigation of heat transfer in a porous convective radiative moving longitudinal fin exposed to magnetic field in the presence of a shape-dependent trihybrid nanofluid

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 197-216页

作者： c.G.PAVITHRA B.j.GIREESHA M.L.KEERTHI Department of PG Studies and Research in Mathematics Kuvempu UniversityShankaraghatta 577451India Department of Mathematics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The thermal examination of a non-integer-ordered mobile fin with a magnetism in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The combination approach is utilized to evaluate the physical and thermal characteristics of the trihybrid and hybrid nanofluids, excluding the thermal conductivity and dynamic viscosity. These two properties are inferred by means of the interpolation method based on the volume fraction of nanoparticles. The governing equation is transformed into a dimensionless form, and the Adomian decomposition Sumudu transform method(ADSTM) is adopted to solve the conundrum of a moving fin immersed in a trihybrid nanofluid. The obtained results agree well with those numerical simulation results, indicating that this research is reliable. The influence of diverse factors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furthermore, the fluctuations in the heat transfer concerning the pertinent parameters are studied. The results show that the heat flux in the presence of the combination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the combination of only spherical and cylindrical nanoparticles. The temperature at the fin tip increases by 0.705 759% when the value of the Peclet number increases by 400%, while decreases by 11.825 13% when the value of the Hartman number increases by 400%.

关键词： convection radiation moving longitudinal fin Adomian decomposition Sumudu transform method(ADSTM) trihybrid nanofluid magnetic field

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Thermoluminescence characterization of natural and synthetic irradiated ce-monazites

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j.urnal of Rare Earths 2024年第4期42卷 643-650页

作者： V.correcher c.Boronat j.Garcia-Guinea j.F.Benavente T.Rivera-Montalvo cIEMAT Av.Complutense 4028040MadridSpain MNcN-cSIc J.Gutierrez Abascal 228006MadridSpain Instituto Politécnico Nacional CICATA-IPNAv.Legaria 694Mexico City11500Mexico

The thermoluminescence(TL)emission of synthetic and natural ce-monazites was characterized here to determine the potential application in the identification of microscopic defects from a qualitative point of view trying to link each TL peak to a chemical-physical *** kinetic parameters that lead the luminescence processes were calculated by means of variable heating rate and computing glow curve deconvolution methods and allow identifying three groups of components at~90,130 and 290℃(for the mineral sample)and~90,170,220,270 and 320℃(for the synthetic cePO_(4):Nd_(0.20),La_(0.25)).The main differences appreciated in these complex TL curves are mainly due to(i)the content of impurities(natural sample contains lanthanides as well as U 0.60%and Th 5.22%)and(ii)the degree of crystallinity of the samples which is directly related to the type of impurities(synthetic monazite relies only on Nd and La).The behavior of the dose response in the range of 1-8 Gy is similar for both samples;the TL intensity increases linearly as the dose increases without changes in the position of the maxima,denoting first-order kinetic luminescence *** peak could be mostly associated with structural defects(i.e.,phase transitions),chemical reactions(i.e.,ce3+?ce4+redox reaction,dehydration or dehydroxylation processes)or intrinsic defects(i.e.,Frenkel defects,ODcs or NBOHcs).

关键词： Thermoluminescence Kineticparameters Phosphate ce-monazite Defects Rare earths

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Degradation and resynthesis of chlorophyll during increased oxidative stress and prolonged darkness differ between annual and perennial flax(Linum L.)

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Oil crop Science 2024年第2期9卷 121-130页

作者： Kenyon j. Nisbett Abida Alokozai Su Hyun Elizabeth Ko G. Adam Mott j.son c.L. Browna Department of Biological Sciences University of Toronto ScarboroughTorontoONCanada Department of cell&Systems Biology University of TorontoTorontoONCanada centre for the Analysis of Genome Evolution&Function University of TorontoTorontoONCanada

Among plants,there is considerable variation in lifespan:annuals live less than one year,whereas perennials live for several years,with the longest-living perennial having survived 43,600 *** proposed by the Disposable Soma Theory,this lifespan variation among plants likely reflects differential investment of limited energy and nutrient resources,with perennials investing more energy and nutrients into biomolecular maintenance compared to annuals in order to ensure persistence over multiple *** differential investment may be particularly important during periods of exogenous stress,which are known to accelerate biomolecular *** present study evaluated this hypothesis using annual and perennial flax(Linum L.)subj.cted to two exogenous stressors—increased oxidative stress(i.e.,foliar H2O2spraying)and complete prolonged *** chlorophyll has been shown to exhibit degradation in response to changes in environmental conditions,we utilized changes in chlorophyll levels during and after periods of exogenous stress to evaluate our *** predicted that i)perennials would exhibit a slower rate of chlorophyll degradation during exposure to exogenous stressors compared to annuals,and ii)perennials would exhibit a faster rate of chlorophyll resynthesis following such exposure compared to *** levels before,during,and after exposure to both exogenous stressors were measured in two separate trails,once using image colour analysis and once using *** chlorophyll degradation rates in response to oxidative stress did not differ between annuals and perennials,contrary to our predictions,chlorophyll resynthesis rates following such exposure were significantly higher in perennials,as *** plants were subj.cted to complete prolonged darkness,chlorophyll degradation rates were significantly lower in perennials than annuals,as predicted;however,when plants were subsequently reintroduced to natural photoperiod,ch

关键词： Ageing Life history Maximum lifespan Oxidative stress Somatic maintenance

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Laser-induced graphene-coated wearable smart textile electrodes for biopotentials signal monitoring

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Frontiers of Materials Science 2024年第1期18卷 95-111页

作者： c.M.Vidhya Yogita Maithani Sakshi Kapoor j.P.Singh Department of Physics Indian Institute of Technology DelhiHauz KhasNew Delhi 110016India

This paper describes how to produce a wearable dry electrode at a reasonable cost and how to use it for the monitoring of biopotentials in *** textiles in wearable technologies have made a great advancement in the health care management and living standards of *** was manufactured using the low-cost single-step process,laser ablation of polyimide,a commercial *** dispersions were made using solvent isopropyl alcohol which has low boiling point,nontoxicity,and environmental *** successive coating of the graphene dispersion on the cotton fabric to make it conductive,the sheet resistance of the resulting fabric dropped to 3% of its initial *** laser-induced graphene(LIG)cotton dry electrodes thus manufactured are comparable to Ag/Agcl wet electrodes in terms of the skin-to-electrode impedance,measuring between 78.0 and 7.2 kΩ for the frequency between 40 Hz and 1 *** LIG cotton electrode displayed a signal-to-noise ratio of 20.17 *** to its comfort,simplicity,and good performance over a longer period of time,the textile electrode appears suited for medical applications.

关键词： biopotential electrocardiogram electromyogram flexible electrode textile porous graphene

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n-Alkane bound biomarker fingerprints from asphaltenes in the bitumens of Eastern Dahomey Basin,Nigeria:Source and genetic implications

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Petroleum Research 2024年第1期9卷 85-91页

作者： Modupe A.Egbeola Olubunmi c.Adeigbe Olaj.de j.Adamolekun Department of Geology University of IbadanIbadanNigeria Structural Geology and Tectonics Institute of Applied GeosciencesKIT-Karlsruhe Institute of TechnologyAdenauerring 20a76131KarlsruheGermany

The asphaltene fractions of the bitumens of Eastern Dahomey Basin in Nigeria,were analyzed by flash pyrolysis-gas chromatography(Py-Gc)method in order to unravel its geochemical history and *** distributions of the initial biomarkers of the original oils from the pyrolysates are related to the assessment of organic matter source,paleo-redox conditions and source environment during ***,it effectively establishes the genetic relationship of the *** n-alkane distributions in the pyrolysates reveal nc_(9)-nc_(32)n-alkanes,maximizing at nc_(14),isoprenoids-pristane(Pr)and phytane(Ph),and some n-alkene *** peaks of low to medium-weight nc_(9)-nc20 n-alkanes and low peaks of nc_(21)+n-alkanes characterize the *** reveal that abundant algal organic matter with some terrigenous inputs contributed to the source rock of the *** high concentration of marine organic matter inputs to the source rock is further confirmed by the nc_(17)/nc27 ratios which range from 5.39 to 19.82 and shows the predominance of nc_(17)*** general unimodal n-alkane distributions in the bitumens indicate derivation from similar organic matter types showing that they are genetically *** anoxic to suboxic environmental conditions that prevailed during the deposition of the sediments is revealed by the isoprenoids,Pr/Ph ratios(0.72-1.28).Pristane/nc_(17)and Phytane/nc_(18)range from 0.16 to 0.33 and 0.22 to 0.56,revealing that the bitumens were from predominantly marine organic matter(type II kerogen)preserved in a reducing environment with no evidence of ***,the Ph/nc_(18)ratio and the cross plot of Pr+Ph/nc_(17)+nc_(18)allow the classification of the bitumens into two subfamilies/groups(A and B).The bitumen samples have low wax content as indicated by the degree of waxiness ranging from 0.21 to 0.38 which confirms low terrigenous *** on the carbon preference index(cPI:0.92 to 1.55)and odd-even predo

关键词： Genetic relationship Flash pyrolysis Biomarker Asphaltene Pyrolysates

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