The effects of system solvent,raw materials molar ratio,catalyst(toluene-p-sulfonic acid) content and accelerator(methanol) content on the yield of DMDBX were studied. The optimized reaction conditions were with cyclohexane/methanol solvent,the molar ratio of(3,4-dimethyl) benzaldehyde to xylitol 2.4∶1.0,the mass fraction of catalyst and accelerator to raw materials 4.0% and 430% respectively.
With the adoption of self-designed ultrasonically enhanced supercritical CO2 reversed microemulsion(USCRM) extraction device, and bis(2-ethylhexyl) sodium sulphosuccinate(AOT) with ethanol as main surfactant and co-surfactant respectively, the extraction of ginsenosides with USCRM was studied, and the effects of ultrasound power and operations were observed.
In order to study the role of supercritical CO2 as a nonaqueous medium in the engineering of biochemical reactions, it is necessary to probe the effects of supercritical CO2 treatment on microbial activity.
The factors that influenced the reaction under microwave heating were investigated,the yield of 82.3% was obtained on condition of ethylene glycol ∶ cyclohexanone = 1.4 ∶ 1(mol/mol),p-toluene sulphonic were investigated acid:2.5 g/mol(based on the amount of cyclohexanone),cyclohexane:80 ml/mol,irradiation power:90 W,13 min.
The effect of the temperature pH,catalyzer and time on the production yield is investigated by orthogonal experiment. The product yield is 42% in the optimal conditions such as 0～5℃, pH9～10, catalyzer perchloric acid and reaction time 20 h.
The catalyst of AlCl3 immobilized on γ-Al2O3 with meso-pore structure was prepared using a two-step method and its catalytic behavior was investigated in the alkylation of benzene with pure 1-octene,1-decene,1-dodecene and industrial alkene mixtures in a suspension bed reactor.
The complex Eu(Sal)2(phen)2(NO3) was synthesized with Eu(NO3)3, salicylic acid and 1,10-phenanthroline as raw materials. The factors influencing on the reaction, such as the amount of ligand and solvent were investigated.
In this paper we give a further investigation of the method introduced by the author in [1, Frequency-domain bounds for nonnegative unsharply band-limited functions] for proving bounds for functions with nonnegative Fourier transforms.
The investigation of $ L^q $ norm Bernstein inequalities $(0>amp;lt;q\leq \infty ), $ for polynomials with unimodular coefficients, leads to unexpected results.
In 1994, Kotz, Ostrovskii and Hayfavi  carried out a detailed investigation of analytic and asymptotic properties of the density of the distribution for the symmetric case θ=0.
The investigation is based on the stability of Riesz bases of cosines and sines in the Hibert space L2[0,π].
In the present investigation, 4-hydroxy-3-methylacetophenone, on condensation with appropriate aldehydes in methanolic potassium hydroxide solution, yielded the corresponding chalcones (CI-XI).
Significant (p?=?0.0061) increases of radioactivity were observed in kidney, spleen, and thyroid, which could be exampled by the effects of the extract and/or by the generation of active metabolites.
This paper investigates the effects of postponing retirement on economic growth in an aging society by using the infinite overlapping generations model constructed by Blanchard (1985) in a simple endogenous growth framework.
This paper is devoted to studying a free boundary problem modeling the effects of drug resistance and vasculature on the response of solid tumors to therapy.
The effects of preparation process on particle size, specific surface area, crystal form and crystalline morphology of the tungsten trioxide was investigated by TEM and XRD etc.
A chemiluminescence technique was applied to study the effects of their scavenging superoxide radicals
In our paper [KR] we began a systematic study of representations of the universal central extension[InlineEquation not available: see fulltext.] of the Lie algebra of differential operators on the circle.
This study was continued in the paper [FKRW] in the framework of vertex algebra theory.
In the present paper we study the remaing nontrivial case, that of a negative central charge-N.
We study reductive group actions on complex affine quadrics.
We study certain naturally-defined analytic domains in the complexified groupHC which are invariant under left and right translation byH?.