Theoretic Ratio Research Articles

Fabrication and characterization of I doped Bi2MoO6 microspheres with distinct performance for removing antibiotics and Cr(VI) under visible light illumination

A solvothermal-calcination process was applied to fabricate a series of novel I doped Bi2MoO6 microspheres. The obtained Ix-Bi2MoO6 microspheres presented outstanding photocatalytic activity for removal of three antibiotics (Tetracycline-TC, ciprofloxacin-CPFX, oxytetracycline hydrochloride-OTTCH) and Cr(VI) under visible-light illumination. The texture and physicochemical properties were investigated by XRD, SEM, TEM, XPS, UV–vis DRS and photo- electrochemical test. After iodine doping, the specific surface area of Bi2MoO6 was obviously increased, which contributed to the enhanced adsorption for antibiotics and Cr6+ in water. In addition, I0.4-Bi2MoO6 (theoretic molar ratio of I to Mo is 0.4) exhibited the highest photocatalytic activity. And after visible-light illumination for 3 h, the removal rates are 88.8%, 90.0% and 89.6% for TC, CPFX, and OTTCH, respectively. Moreover, I0.4-Bi2MoO6 possesses the distinct activity for removing Cr(VI) in water.

Sulfide Precipitation in Wastewater at Short Timescales

Abatement of sulfides in sewer systems using iron salts is a widely used strategy. When dosing at the end of a pumping main, the reaction kinetics of sulfide precipitation becomes important. Traditionally the reaction has been assumed to be rapid or even instantaneous. This work shows that this is not the case for sulfide precipitation by ferric iron. Instead, the reaction time was found to be on a timescale where it must be considered when performing end-of-pipe treatment. For real wastewaters at pH 7, a stoichiometric ratio around 14 mol Fe(II) (mol S(−II))−1 was obtained after 1.5 s, while the ratio dropped to about 5 mol Fe(II) (mol S(−II))−1 after 30 s. Equilibrium calculations yielded a theoretic ratio of 2 mol Fe(II) (mol S(−II))−1, indicating that the process had not equilibrated within the span of the experiment. Correspondingly, the highest sulfide conversion only reached 60%. These findings differed significantly from what has been demonstrated in previous studies and what is attained from theoretical equilibrium conditions.

Therapeutic supermolecular micelles of vitamin E succinate-grafted ε-polylysine as potential carriers for curcumin: Enhancing tumour penetration and improving therapeutic effect on glioma

Severe toxicity and poor tumour penetration are two intrinsic limited factors to hinder the broad clinical application for most of first-line chemotherapeutics. In this study, a novel vitamin E succinate-grafted ε-polylysine (VES-g-PLL) polymer was synthesized by using ε-polylysine as backbone. By adjusting VES graft ratio, VES-g-PLL (50) with a theoretic VES graft ratio of 50% could self-assemble into a supermolecular micelle with a hydrodynamic diameter (Dh) of ca.20nm, and Zeta potential of 19.6mV. VES-g-PLL micelles themselves displayed a strong anti-tumour effect on glioma. The poorly water-soluble curcumin was effectively encapsulated in VES-g-PLL micelles with the drug loading amount and entrapment efficiency reaching 4.32% and 82.27%, respectively. In a physiologic medium, curcumin-loaded VES-g-PLL micelles (Cur-Micelles) not only remained stable without obvious drug leakage but also sustained the release of its encapsulated curcumin for a long time. Because of the ultra-small size and positively-charged surface, Cur-Micelles penetrated the deeper tumour zone than free curcumin, resulting in a significant inhibition of tumour spheroids growth. Moreover, in vivo strong antitumor effect of Cur-Micelles was also exhibited at assistance of ultrasound-targeted microbubble destruction and the real-time MRI imaging demonstrated a nearly complete suppression of glioma after 28days of treatment. TUNEL staining showed that the therapeutic mechanism of Cur-Micelles was relevant to the apoptosis of tumour cells. Finally, in vivo nontoxicity of Cur-Micelles against normal organs including heart, liver, spleen, lung and kidney tissues was also demonstrated by the HE staining. In conclusion, VES-g-PLL micelles may serve as a potential carrier for curcumin to enhance tumour penetration and improve therapeutic effect on glioma.

The Entropic Linkage between Equity and Bond Market Dynamics

An alternative derivation of the yield curve based on entropy or the loss of information as it is communicated through time is introduced. Given this focus on entropy growth in communication the Shannon entropy will be utilized. Additionally, Shannon entropy’s close relationship to the Kullback–Leibler divergence is used to provide a more precise understanding of this new yield curve. The derivation of the entropic yield curve is completed with the use of the Burnashev reliability function which serves as a weighting between the true and error distributions. The deep connections between the entropic yield curve and the popular Nelson–Siegel specification are also examined. Finally, this entropically derived yield curve is used to provide an estimate of the economy’s implied information processing ratio. This information theoretic ratio offers a new causal link between bond and equity markets, and is a valuable new tool for the modeling and prediction of stock market behavior.

Simple New Method to Predict Bear Markets (The Entropic Linkage between Equity and Bond Market Dynamics)

An alternative derivation of the yield curve based on entropy or the loss of information as it is communicated through time is introduced. Given this focus on entropy growth in communication the Shannon entropy will be utilized. Additionally, Shannon entropy’s close relationship to the Kullback–Leibler divergence is used to provide a more precise understanding of this new yield curve. The derivation of the entropic yield curve is completed with the use of the Burnashev reliability function which serves as a weighting between the true and error distributions. The deep connections between the entropic yield curve and the popular Nelson–Siegel specification are also examined. Finally, this entropically derived yield curve is used to provide an estimate of the economy’s implied information processing ratio. This information theoretic ratio offers a new causal link between bond and equity markets, and is a valuable new tool for the modeling and prediction of stock market behavior.

충돌벽면이 직분식 LPG의 분무 및 연소 특성에 미치는 영향에 관한 실험 연구

As an alternative fuel that can be used in SI engine, LPG is one of clean fuels with larger H/C ratio compared to gasoline, low <TEX>$CO_2$</TEX> emission, and small amount of pollutants such as sulfur compounds. When LPG is used in spark ignition engine, volumetric efficiency of the engine can be improved and pumping loss can be reduced by performing direct injection into the combustion chamber instead of port fuel injection. LPG-DI engine allows for lean combustion and stratified combustion under low load. In case of stratified combustion, air fuel ratio can be greatly increased compared to theoretic mixture ratio combustion. Improved thermal efficiency of the engine and reduced pumping loss can be expected from stratified combustion. Accordingly in this study, an experimental apparatus for visualization was designed and manufactured to study the combustion process of LPG after injection and ignition, intended to examine ignition probability and combustion characteristics of spark ignition direct injection(SIDI) LPG fuel. Ambient pressure, ambient temperature and fuel injection pressure were found as important variables that affect ignition probability and flame propagation characteristics of LPG-air mixture. Also, it was verified that the injected LPG fuel can be directly ignited by spark plug under appropriate ambient conditions.

Effect of replacement of Ca by Ln (Ln = Y, Gd) on the structural and luminescence properties of CaWO4:Eu3+ red phosphors prepared via co-precipitation

Eu3+-doped calcium based tungstate, Ca1−xLnxWO4:Eu3+ (Ln=Y, Gd) red-emitting phosphors were prepared by co-precipitation method with NH4HCO3–NH3·H2O system as the precipitating aid agent. X-ray diffraction results reveal that the synthesized Ca1−xLnxWO4:Eu3+ have scheelite structure with pure phase. Infrared spectra show strong absorption peaks between 803 and 440cm−1 which are assigned to the vibration of O–W in WO42− tetrahedron. The Energy Disperse Spectroscopy analysis reveals that the red phosphors have been successfully prepared by co-precipitation method according to theoretic ratio. Due to the 5D0–7F1–3 transitions of Eu3+ ions, photoluminescence spectra show a red emission at about 614nm under excitation of 395nm (commercial ultraviolet) and 465nm (blue chip). With Ln lanthanide added in host, the luminescent intensity of Ca1−xLnxWO4:Eu3+ (x=0.4, 0.5) is obviously improved comparing with that of CaWO4:Eu3+ by several times.

Analysis of Bridge-Type Nano-Positioning Stage

A piezoelectric nanostage using bridge-type flexure hinge mechanisms is developed. Elastic beam theory was used to analyze the ideal and theoretic displacement amplification ratio and find that their value is mainly influenced by the length of the tilt rod and tilt angle of bridge-type. A multilayer S-type hinge is designed as the prismatic of moving platform. Stiffness and natural frequency model of the whole stage is built and find out that their value is mainly relevant to hinge thickness, tilt angle of bridge-type hinge and length of S-type hinge. Finally, finite element method (FEM) is used to verify the drived model. The errors of the total stiffness and the natural frequency of the stage between FEM and theory analysis are 3.8% and 6.6% respectively, which confirm the predictions of theory analysis.

Co-precipitation synthesis and photoluminescence properties of (Ca 1− x− y,Ln y)MoO 4: xEu 3+ (Ln = Y, Gd) red phosphors

(Ca 1− x− y ,Ln y )MoO 4: xEu 3+ (Ln = Y, Gd) red phosphors were prepared by co-precipitation method with NH 4HCO 3–NH 3·H 2O system as the precipitating agent. X-ray diffraction (XRD), Fourier transform infrared spectrometer (FT-IR), and energy-dispersive X-ray spectrometer (EDS) were used to characterize the structure and composition of the phosphors. The synthesized (Ca 1− x− y ,Ln y )MoO 4: xEu 3+ have scheelite structure with pure phase. FT-IR spectra show strong absorption peaks between 914 and 730 cm −1 which are assigned to the vibration of O–Mo–O in MoO 4 2− tetrahedron. The EDS analysis reveals that the red phosphors have been successfully prepared by co-precipitation method according to theoretic ratio. Photoluminescence spectra show a red emission around 614 with 394 and 464 nm excitation, which is match well with the output wavelength of commercial ultraviolet and blue LED chips. The luminescent intensity of (Ca,Ln)MoO 4: Eu 3+ is obviously higher than that of CaMoO 4: Eu 3+.

Viral hepatitis-associated intrahepatic cholangiocarcinoma shares common disease processes with hepatocellular carcinoma

Bile duct cells and hepatocytes differentiate from the same hepatic progenitor cells. To investigate the possible association of viral hepatitis B and C with intrahepatic cholangiocarcinoma (ICC), we conducted a retrospective case–control study using univariate and multivariate logistic analyses to identify risk factors for ICC. Besides hepatic lithiasis (25.6%; P<0.001), seropositivity for hepatitis B surface antigen (37.5% of all ICC patients; odds ratio (OR) =4.985, P<0.001) and seropositivity for hepatitis C antibodies (13.1%; OR=2.709; P=0.021) are the primary independent risk factors for ICC. Cirrhosis exerted synergic effects on the development of ICC. We compared the age distributions of viral-hepatitis associated ICC to that of viral hepatitis-associated hepatocellular carcinoma (HCC). The mean age of ICC patients with viral hepatitis B (56.4±11.1 years) were 9 years younger than that of ICC patients with viral hepatitis C (65.6±9.17 years), similar to that observed in HCC. The incidence ratio of HCC : ICC : CHC (combined hepatocellular cholangiocarcinoma) in our population was 233 : 17 : 1 consistent with the theoretic ratio of hepatocyte number to cholangiocyte number in the liver. Our findings indicated that both viral hepatitis-associated ICC and HCC shared common disease process for carcinogenesis and, possibly, both arose from the hepatic progenitor cells.

Analysis of the displacement amplification ratio of bridge-type flexure hinge

The bridge-type flexure hinge is a classic displacement amplification mechanism. The existing models of theoretic displacement amplification ratio of bridge-type flexure hinges are not perfect. This makes it very difficult to design and manufacture a satisfactory structure using these models. Kinematic theory was used to analyze the ideal displacement amplification ratio of a bridge-type flexure hinge in this paper, and the flexure hinge was regarded as a pure multi-rigid body with ideal pivots. Elastic beam theory was used to analyze the theoretic displacement amplification ratio when considering the translational and rotational stiffness of the flexure pivots. The model of theoretic displacement amplification ratio explains why the bridge-type displacement amplification mechanism has an amplification ratio extremum and where the threshold is. The finite element method was used for comparison with the mathematical model, and similar results were obtained. Finally, the finite element method was used to analyze the shape mode of the structure. The result showed that increasing the amplification ratio by decreasing the thickness of the flexure pivots led to a decrease in the mode shape frequency of the bridge-type structure. Thus, redesigning of the structure was needed to solve the problem.

Test of the information theory of branching ratios by classical trajectory computations

Extensive classical trajectory calculations are reported for the system F + HD → HF + D or DF + H, over a wide variety of initial conditions. The results of these computations are used to assess the utility of the information theoretic approach to the prediction of the initial-state dependence of the branching ratio, Γ HF/DF. Two distinct forms for the information theoretic branching ratio are considered, corresponding to two different choices of constraints upon the transition probability matrix. The constraints in question are the “model” constraint employed by Kaplan and Levine, and the “direct” constraint, a generalisation of that introduced by Levine and Kosloff. The two forms of information theory give satisfactory predictions under selected (differing) initial conditions. Neither form is clearly superior. In particular, both fail to predict the observed trend of Γ HF/DF with initial rotational state J, for the case of thermally averaged initial translational energies. This failure is linked to an important “interbranch constraint” not incorporated in the theory, stemming from the different activation energies for formation of the two products.

Franck–Condon factors in studies of the dynamics of chemical reactions. III. Analysis of information theory for vibration–rotation distributions and isotopic branching ratios

A previously developed approximate theory of chemical dynamics based on generalized Franck–Condon factors is used to study the information theoretic analysis of vibration–rotation distributions and of isotopic branching ratios. We begin by examining the surprisal function I obtained from the Franck–Condon factors for rotational and vibrational distributions. For rotational distributions we find linear surprisal behavior for low rotational excitation in the limit of strong potential and weak kinematic coupling, but nonlinear surprisals for high rotational excitation in that limit. In addition, nonlinear rotational surprisals are generally obtained for any degree of rotational excitation in the limit of strong kinematic and weak potential coupling. We find these generalizations from the Franck–Condon factors and their applications to the H+H2, F+H2(D2), and H+Cl2 reactions. For F+H2(D2), nearly microcanonical rotational distributions are obtained (for low j′), due to the cancellation of contributions from the angular coordinate overlap factor [which leads to a positive slope (temperature) parameter ϑ] and centrifugal stretching effects (which lead to negative ϑ). For vibrational distributions linear surprisals are obtained for F+H2(D2), where little of the reaction exoergicity is released in the exit channel and the region of maximum overlap of reagent and product wavefunctions is highly localized, but not for H(D)+Cl2, which has a higher repulsive energy release (in the terminology of Polanyi and co-workers) and a more delocalized overlap. For both rotational and vibrational surprisals, we find that linearity occurs when the potential constrains the reaction to occur through a highly localized set of nuclear configurations (and hence in the limit of strong potential coupling and of highly localized overlaps). In our study of branching ratios, we consider the isotopic branching in F+HD→FH(FD)+D(H). We first show that the purely dynamical Franck–Condon factor provides a correct qualitative description of the branching ratio (especially its dependence on reagent rotational excitation). We then use information theory to predict the same ratio, and find some points of similarity to the purely dynamical result (such as the dependence on parameters of the product state distributions), but also certain important points of difference (such as dependence on degree of reagent rotational excitation). These points of similarity and difference may be reinterpreted in terms of the relative contribution of strongly coupled potential and kinematic effects, respectively, and the success of simple information theoretic branching ratio predictions depends on the relative importance of these factors.

Computational studies of reactive/non-reactive branching ratios for a simple model system

Reactive/non-reactive branching ratios and the energy distribution in both branches were computed using analytical classical mechanics for an idealized collinear collision. The trajectory generated branching ratios are compared with the predictions of an information theoretic approach assuming only knowledge of the products state distribution. Over a wide range of variations in energy distribution in the reactants, vibrational energy spacings and the major topography of the potential energy surface it is found that the information theoretic branching ratio is invariably in qualitative accord with the direct computation.