Miracle-dz/UniFAR-FTUs huggingface dataset:
Multiobjective decision processes under uncertainty : Applications, problem formulations, and solution strategies

We consider the decision-making problems that firms face when operating in a changing and uncertain environment. Problems of this type arise in many important decision contexts in various industries and pose challenges for both practitioners and researchers. This paper is a contribution to the development of a general framework for formulating and solving this class of problems through an investigation of current applications and solution methodologies. We consider a general class of problems: multiobjective decision processes under uncertainty, with concentration on its application areas, problem formulations, and solution strategies. A morphology classifies the relevant literature by projecting the problems reported onto a multidimensional problem space. A problem of coordinated capacity planning and inventory control serves as an example of this problem class to illustrate the issues related to formulations and solutions throughout the paper. We develop an approximation architecture that decomposes th.
Theoretical Study of Oxygen Adsorption on Graphite and the (8,0) Single-walled Carbon Nanotube

Spin-polarized density functional calculations are used to study the adsorption of O atoms and O2 molecules on graphite and on a (8,0) single-walled carbon nanotube. An O atom is found to bind to graphite and to the outside and inside surfaces of the nanotube to give stable epoxide-like structures. Of these, the most stable is the epoxide on the outer surface of the nanotube, with a calculated adsorption energy of 44 kcal/mol. In the case of O2, both physisorbed and chemisorbed species are identified. The O2 molecule is predicted to only weakly physisorb (adsorption energy ≈ 0.9 kcal/mol) to the graphite and the (8,0) nanotube surfaces. However, these adsorption energies are expected to be underestimated due to inadequate treatment of the dispersion interactions. The chemisorbed species are metastable in the sense that they lie energetically above the isolated X 3Σg+ O2 and graphite or nanotube systems. In the case of the outer wall of the nanotube, the chemisorbed species is predicted to lie only 10.2 kc.
Silicon incorporation in CVD diamond layers

The silicon incorporation in diamond is an important issue as silicon is widely used as a substrate for the growth of polycrystalline thin films. Incorporated silicon impurities are suspected to come from the hydrogen etching of the silicon substrate. To clearly establish this point we introduced a solid source of silicon during the growth of a homoepitaxial diamond layer on a HPHT diamond substrate. A quantitative SIMS analysis revealed concentrations of silicon up to 3 × 1019 cm–3 in the diamond layer. Then we propose a scenario for the contamination of polycrystalline diamond grown on silicon substrates: after nucleation, the progressive paving of the silicon surface by 3D grains causes a fast decrease of its incorporation. At coalescence, the silicon substrate is completely covered by a 2D diamond film and the silicon concentration in diamond reaches a residual level. The investigated MPCVD and HFCVD diamond layers grown on silicon substrates present comparable features. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Interplay of Search and Gradient Descent in Semi-stationary Learning Problems

We explore the interplay of generate-and-test and gradient-descent techniques for solving online supervised learning problems. The task in supervised learning is to learn a function using samples of inputs to output pairs. This function is called the target function. The standard way to learn non-linear target functions is to use artificial neural networks, where the weights of the network are learned via the backpropagation algorithm. The conventional backpropagation algorithm consists of two parts: initializing weights with small random numbers, and gradient descent at every time step. We consider a case that differs slightly from most supervised learning in two ways. First, it is conventionally assumed that the samples are independently and identically distributed, whereas we focus on the case where the samples are temporally coherent. Second, it is often assumed that the learner has sufficient capacity to closely approximate the target function, whereas we assume that the target function is more complex than the learner. Our case is interesting because the real world is often temporally coherent and extremely complex. Temporal coherence means that samples at consecutive time steps are not independent; rather, the new sample depends on the previous samples. We call the class of problems with stationary target functions but temporally coherent input, semi-stationary learning problems. We focus on semi-stationary problems where the target function is more complex than the learner. We use a novel idealized problem to study various solution methods. In the problem, the inputs follow a Markov chain, and the target function is represented by ii a multi-layered network, which allows us to control the relative complexity of the target function and the approximator. In our idealized problem, the best approximation continually changes because of temporal coherence and the high complexity of the target function. Because of this, there is a need for continual learning/adaptation. We use the conventional backpropagation algorithm to track the best approximation. However, this algorithm is temporally asymmetric in that it treats the beginning of time differently, as the computation to generate small random weights only happens at the first time-step. Surprisingly, this makes conventional backpropagation unsuitable for continual learning. We show that backpropagation performs well initially on our idealized problem, but that its performance decays substantially over time and it loses the ability to adapt. Finally, we propose a solution to the decaying adaptiveness of backpropagation that continually injects random features alongside gradient descent. We use a generate-and-test process to inject random features. Our generate-andtest process replaces low utility features with random features from the initial distribution. We find that this continual injection of randomness significantly improves the adaptiveness and performance of gradient descent.
The S1–S0 transition of indole and N‐deuterated indole: Spectroscopy and picosecond dynamics in the excited state

A vibrational analysis for the excitation and fluorescence spectra of the S1–S0 transition in jet‐cooled indole and N‐deuterated indole is presented. This analysis yields the frequencies for eight low‐lying S1 vibrational modes of both isotopic species. Single vibronic level fluorescence spectra also enable us to refine many of the S0 vibrational frequencies. Quantum interference effects in the energy‐resolved fluorescence decays for one vibrational level of S1 indole are observed as a result of picosecond laser excitation. Through analysis of the fluorescence spectra and the modulated fluorescence decays, the coupling responsible for the quantum beats was found to result from a zero‐order in‐plane mode coupled to a level which is described by several zero‐order out‐of‐plane modes. The effect of the deuterium substitution on the quantum beats is also investigated.
Study of Two-Photon Absorption Spectral Property of a Novel Nonlinear Optical Chromophore Using Femtosecond Continuum

The degenerate two-photon absorption (TPA) spectrum has been studied for a novel organic chromophore (AF389) that exhibits extremely high TPA cross-section values around the ∼800 nm range in both nanosecond and femtosecond domains. To measure the direct degenerate TPA spectrum of AF389 in the femtosecond regime, we have developed a new technique that is based on the use of a single continuum-generation beam as an intense coherent white-light source for TPA excitation. The different spectral components of the input continuum beam are spatially dispersed and then pass the sample through different pathways so that nondegenerate TPA processes among different spectral components can be avoided. Our results show that the TPA spectrum of AF389 is different from the linear absorption spectrum on the scale of absorbing photon energy. There is a significant blue shift of the absorption peak position for the TPA spectrum with respect to the linear absorption spectrum, indicating that the transition pathways are diff.
Aggregation of ferrihydrite nanoparticles in aqueous systems

Crystal growth by non-classical mechanisms, such as oriented aggregation, frequently involves an aggregation step. The aggregation of nanoparticles is sensitive to solution variables like ionic strength and pH, as well as the presence and concentration of other chemical species. Aggregation is a critical first step during the early stages of oriented aggregation. Time-resolved, cryogenic transmission electron microscopy was employed to characterize the degree of aggregation, the reversibility of aggregation, and the influence of additives on aggregation in aqueous suspensions. In this work, freshly synthesized ferrihydrite nanoparticles in aqueous suspension were employed as the model system. These nanoparticles are largely aggregated even with a solution pH several pH units away from the point of zero net proton charge (PZNPC) and a very low ionic strength (<10−4 M). Reversibility of aggregation was observed to be time-dependent. Finally, chemical additives dramatically change the evolution of aggregation state with strongly coordinating ligands strongly suppressing aggregation, even after aging at an elevated temperature.
Cadmium and health: a survey

Cadmium is a toxic heavy metal which is widely present in our environment. Recent investigations suggest that cadmium levels in the environment are rising as a result of increased industrial use. The elimination of cadmium from the body takes place at an extraordinary low rate, so that the metal accumulates in the body, primarily in the liver and kidneys. When cadmium concentration in the kidney cortex becomes sufficiently high a tubular kidney dysfunction is induced. Newly born are practically free from cadmium, while a middle‐aged man carries a cadmium concentration in the kidney cortex of about 20 μg Cd/g. However, the variation in individual concentrations is large; this means that some people in larger populations may already have cadmium concentrations in the renal cortex close to the critical level.
Extraframework species in zeolite Y at nonambient conditions

Zeolites are crystalline aluminosilicates, composed of corner-sharing AlO4 and SiO4 tetrahedra joined into three-dimensional frameworks having pores of molecular dimensions. Zeolite Y (faujasite, FAU) is the zeolite used on the largest scale for catalytic applications. As part of a multitechnique analytical program aimed at characterizing ion-exchanged faujasites, many sieves were characterized using synchrotron powder diffraction techniques. The dehydrated starting materials Na-FAU and NH4-FAU were studied at 20 K, as well as a Xe-containing dehydrated Na-FAU (129Xe NMR is often used to study diffusion and porosity of zeolites). The structures of NH4-FAU and H-FAU were characterized as a function of framework aluminum concentration. Ca,Na-FAU, La,Na-FAU, Ba,Na-FAU, and Zn,Na-FAU were characterized both at ambient conditions (hydrated) and at 300°C (dehydrated). To characterize the Zn,Na-FAU, Zn-edge resonant scattering experiments were carried out both at room temperature and at 300°C. An important part .
Electrosynthesis and characterization of biotin-functionalized poly(terthiophene) copolymers, and their response to avidin

Using a succinyl ester linker, a terthiophene bearing a pendant biotin hydrazide in the 3′ position (4-{N′-[5-(4,6-dioxo-hexahydrothieno[3,4-c]pyrrol-3-yl)-pentanoyl]hydrazino}-4-oxo-butyric acid 2-[2,2′:5′,2″]terthiophen-3′-yl-ethyl ester, 4) has been prepared in three steps from 2-[2,2′:5′,2″]-terthiophen-3′-yl-ethanol, 2, via succinic acid mono-(2-[2,2′,5′,2″]-terthiophene-3′-yl-ethyl) ester, 3. Using the ‘oligomer as monomer’ approach, polyterthiophene (co)polymer films have been generated, on Pt, Au and ITO-coated glass working electrodes, by repetitive scan cyclic voltammetry of solutions of 2,2′:5′,2″-terthiophene, or either 3 or 4 along with 2,2′:5′,2″-terthiophene itself. These films have been characterized by cyclic voltammetry (CV), electrochemical impedance spectra (EIS) and in situ reflectance FTIR spectroscopy. FTIR spectroscopy suggests that the 2,2′:5′,2″-terthiophene : 4 copolymer contains intact biotin moieties. The incubation of poly-2,2′:5′,2″-terthiophene and 2,2′:5′,2″-terthiophene : 4 copolymer with aqueous buffer solutions, followed by transfer back to CH3CN/0.1 M TEAT, results in only small changes in the film CV, whereas exposure of the biotin-functionalized 2,2′:5′,2″-terthiophene : 4 copolymer to avidin causes drastic changes to its CV and its EIS, consistent with the binding of avidin by biotin resulting in restricted ion transfer to and from the polymer. The minimum amount of avidin which causes a detectable change in the electrochemistry of a 0.03 cm2 2,2′:5′,2″-terthiophene : 4 copolymer-modified electrode is 5 × 10−14 moles. Exposure of the 2,2′:5′,2″-terthiophene : 4 copolymer to excess bovine serum albumin in buffer causes only the same small changes in its electrochemistry as exposure to buffer alone, ruling out nonspecific adsorption as a cause of the electrochemical changes on avidin exposure.
Specific and nonspecific cation adsorption to clays: solution concentrations and surface potentials

A model for cation adsorption to negatively charged surfaces is developed by taking into account specific cation binding to the surface sites and adsorption in the double layer region. Equations are given for any combination of mono and divalent cations in solution and for one type of binding site. Variations in solution concentrations of cations due to adsorption are explicitly included in the model in the framework of an iterative procedure. The results indicate that a Langmuir type of adsorption isotherm may represent the data over a certain range of cation concentrations. When a certain cation is present in such small concentrations that it does not affect the surface potential, then an increase in its concentration results in a proportional increase in its adsorbed amount. For a wide range of concentrations the amount of cation adsorbed appears to be independent of its concentration in solution. However, the adsorbed amounts are very sensitive to cation competition. An increase in the concentration of surface sites results in as reduction in the fractional binding per sits. A source of difference between sorption and desorption of cations is explained.
Uranium Uptake from Aqueous Solution by Interaction with Goethite, Lepidocrocite, Muscovite, and Mackinawite: An X-ray Absorption Spectroscopy Study

The retention of radionuclides by interaction with mineral phases has significant consequences for the planning of their short- and long-term disposal to geological systems. An understanding of binding mechanisms is important in determining the ultimate fate of radionuclides following release into natural systems and will give increased confidence in predictive models. X-ray absorption spectroscopy (XAS) has been used to study the local environment of uranium taken up from aqueous solution by the surfaces of goethite, lepidocrocite, muscovite, and mackinawite. On both iron hydroxides uranium uptake occurs by surface complexation and ceases when the surface is saturated. The muscovite surface does not become saturated and uptake increases linearly suggesting formation of a uranium phase on the surface. Uranium uptake on mackinawite also suggests a replacement or precipitation process. XAS indicates that bidentate inner-sphere surface complexes are formed on the iron hydroxides by coordination of two surfac.
New Developments in Flow Injection/Sequential Injection On‐line Separation and Preconcentration Coupled with Electrothermal Atomic Absorption Spectrometry for Trace Metal Analysis

Abstract During the last 30 years, flow injection analysis has gone through three generations, that is, the first generation in 1970s, supplemented by sequential injection in the 1990s as the second generation, and the recently emerged lab‐on‐valve system as the third generation, which holds clear advantages for instrumental miniaturization. The three generations have revolutionized the concept of sample pretreatment by facilitating on‐line operation and coupling with various detection techniques, among which its hyphenation with electrothermal atomic absorption spectrometry (ETAAS) has been one of the most attractive research field offering vast potentials and versatilities in the quantification of ultra‐trace metal species in complex matrices. In the present mini‐review, the state‐of‐the‐art developments for flow injection on‐line sample pretreatment coupled to ETAAS for trace metal analysis since 2003 were summarized, with special emphasis on the exploitations of the lab‐on‐valve system.
Synthesis and Biological Evaluation of Laxiflorin J Derivatives as Potential Antitumor Agents

Laxiflorin J, isolated from the leaves of Isodon eriocalyx var. laxiflora, showed significant inhibitory activity toward T-24 cells. A series of laxiflorin J derivatives were synthesized and their in vitro activity was evaluated against BEL-7402, A-549, HT-29, HL-60, MOLT-4 tumor cell lines, with IC50 values ranging from 1.3 to 42.2 mu g mL-1.
Growth saturation of unstable thin films on transverse-striped hydrophilic-hydrophobic micropatterns

Using three-dimensional numerical simulations, we demonstrate the growth saturation of an unstable thin liquid film on micropatterned hydrophilic–hydrophobic substrates. We consider different transverse-striped micropatterns, characterized by the total fraction of hydrophilic coverage and the width of the hydrophilic stripes. We compare the growth of the film on the micropatterns to the steady states observed on homogeneous substrates, which correspond to saturated sawtooth and growing finger configurations for hydrophilic and hydrophobic substrates, respectively. The proposed micropatterns trigger an alternating fingering–spreading dynamics of the film, which leads to a complete suppression of the contact line growth above a critical fraction of hydrophilic stripes. Furthermore, we find that increasing the width of the hydrophilic stripes slows down the advancing front, giving smaller critical fractions the wider the hydrophilic stripes are. Using analytical approximations, we quantitatively predict the growth rate of the contact line as a function of the covering fraction, and predict the threshold fraction for saturation as a function of the stripe width.
The thermoelastic properties of MgSO4·7D2O (epsomite) from powder neutron diffraction and ab initio calculation

time-of-flight powder neutron diffraction has been used to measure the molar volume of MgSO4.7D(2)O (i) from 1.8 - 300 K at ambient pressure, (ii) from 50 - 290 K at 1.4, 3.0, and 4.5 kbar, (iii) from 0 - 5.5 kbar at 290 K, and (iv) from 0 - 4.5 kbar at 50 K. The data have allowed us to determine the temperature dependence of the incompressibility, (partial derivative K/partial derivative T)(p), (thermodynamically equivalent to the pressure dependence of the thermal expansion, (partial derivative alpha/partial derivative P)(T)) of epsomite throughout its stability field. We observed that the a-axis exhibits negative thermal expansion, alpha(a), from 30 - 250 K at room pressure, turning positive above 250 K and being zero below 30 K. However, each of the crystallographic axes exhibits a sharp change in (partial derivative alpha/partial derivative T) at similar to 125 K, and this appears to correspond to significant changes in the axial incompressibilities with the a- and c-axes softening, and the b-axis stiffening considerably below similar to 125 K. Our thermoelastic results are in agreement with ab initio calculations at zero Kelvin; however the calculations offer no obvious insight into the mechanism responsible for the change in behaviour at low temperature.
Synthesis of Calcium Phosphate/Gypsum Composite Powders

Gypsum powders and calcium phosphate/gypsum powders were synthesized by wet method. The influences of the pH and temperature on the morphology of the gypsum crystal were studied by light microscopy. The effects of the initial calcium/phosphorus molar ratio and the pH of the solution on the microstructure and phase composition of the calcium phosphate/gypsum composite powders were studied by scanning electron microscopy and X-ray diffractometry. The results show that both temperature and pH value had influence on the crystal shape of gypsum and the pH value was the predominant parameter for the particle shape and phase composition of the composite powders.
New Approach to Determination of Phenoxyl Free Radicals by Stopped‐Flow Spectrofluorimetry

Abstract A simple and highly sensitive method to quantify the rates of production of phenoxyl radicals in enzyme reaction is described. This method employs the peroxidase‐catalyzed reaction between chlorophenols and hydroperoxide to generate phenoxyl free radicals, which can enhance dimerization of L‐tyrosine. The product, dityrosine, was monitored fluorometrically at the excitation/emission wavelength of 320/410 nm and the initial rate of accelerated‐accumulation of dityrosine represents the formation rate of phenoxyl free radicals. With this method, the phenoxyl radicals generated in oxidation of chlorophenols with hydrogen peroxide, catalyzed by horseradish peroxidase, were investigated. Phenoxyl radicals generated from as low as 5.0×10−9 M 2,4‐dichlorophenol, for example, can be readily detected with a relative standard deviation of 2.6% for 9 replicated determination. The detection limits of phenoxyl radicals produced by various chlorophenols are 4.2×10−9, 1.1×10−9, 1.0×10−10, 2.8×10−8, and 1.1×10−7 M for 2‐chlorophenol, 4‐chlorophenol, 2,4‐dichlorophenol, 2,4,6‐trichlorophenol, and 2,3,4,6‐tetrachlorophenol, respectively. The possible pathway of the reaction is proposed. The protocol is suitable for quantification of free radicals in enzyme reaction and shows promise in being applied to biological systems.
Crystal structure of N,N’-ethylene-bis(1,3-dimethyl-5-pyrazolethiolatoiminomethyl) copper(II), C14H18CuN6S2

C 14 H 18 CuN 6 S 2 , triclinic, P 1(No. 2), a = 8.474(1)Å, b = 12.417(1)Å, c = 8.2077(9) Å, (cid:4) = 99.115(7)°, (cid:1) = 102.094(9)°, (cid:11) = 91.875(9)°, V = 831. 9Å 3 , Z = 2, R gt (F) = 0.038, wR ref (F 2 ) = 0.103, T = 293 K.