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The role of green supplier evaluation and selection (GSES) in supply chain management is increasingly appreciated due to the intensification of competition, raising public consciousness, and environmental issues. To improve GSES, a large number of approaches have been proposed in the past decades. However, few attempts have been made to systematically review and classify the literature in this field. The objective of this study is to afford a comprehensive review of the studies which aim to develop models and methods in helping enterprises to assess and select the right green suppliers. To achieve this goal, a total of 193 journal articles extracted from the Scopus database over the period of 2009 to 2020 were chosen and reviewed. These publications were classified into ten categories based on their adopted GSES models and analyzed concerning the evaluation criteria, criteria weighting methods, and performance evaluation methods. Moreover, a bibliometric analysis was conducted according to the frequency of supplier selection methods, citation number, publication year, journal, country, and application area. This study supports practitioners, managers, and researchers in effectively recognizing and applying the GSES models to enhance organizational competitiveness and provides an insight into its state of the art.

As temperature increases, the thermal vacancy concentration in pure metals dramatically increases and causes some strongly non-linear thermodynamic behaviors in pure metals when close to their melting points. In this paper, we chose body-centered cubic (bcc) W as the target and presented a thermodynamic model to account for its Gibbs energy of pure bcc W from 0 K to melting point by including the contribution of thermal vacancy. A new formula for interaction part was proposed for describing the quadratic temperature behavior of vacancy formation energy. Based on the experimental/first-principles computed thermodynamic properties, all the parameters in the Gibbs energy function were assessed by following the proposed two-step optimization strategy. The thermodynamic behaviors, i.e., the strong nonlinear increase for temperature dependence of heat capacities at high temperatures and a nonlinear Arrhenius plot of vacancy concentration, in bcc W can be well reproduced by the obtained Gibbs energy. The successful description of thermal vacancy on such strongly non-linear thermodynamic behaviors in bcc W indicates that the presently proposed thermodynamic model and optimization strategy should be universal ones and are applicable to all other metals.

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Generally, compound-specific isotope analysis of steroids is carried out by gas chromatography combined with isotope ratio mass spectrometry. Thus, a derivatization of the steroids prior to the measurement is compulsory, and a correction of the isotopic data is often necessary. To overcome this limitation, we present a new approach of high-temperature liquid chromatography coupled with photodiode array detection and isotope ratio mass spectrometry (HT-LC/PDA/IRMS) for the carbon isotope ratio analysis of unconjugated steroids. A steroid mixture containing 19-norandrosterone, testosterone, epitestosterone, androsterone, and 5β-pregnane-3α,17α,20α-triol was fully separated on a C4 column under high-temperature elution with water as the sole eluent. The accuracy for isotope analysis (±0.5 ‰) was around 20 μg g(-1) for testosterone, epitestosterone (79 ng steroid absolute on column), and 30 μg g(-1) for 19-norandrosterone, androsterone, and 5β-pregnane-3α,17α,20α-triol (119 ng steroid absolute on column). The applicability of the method was tested by measuring a pharmaceutical gel containing testosterone. With this work, the scope of LC/IRMS applications has been extended to nonpolar compounds.

In this paper, the concept of anisotropic atomic mobility is first developed in the framework of CALPHAD approach, and atomic mobility descriptions of Li ions in the layered O3 Li x CoO 2 are then assessed based on the experimental self/ tracer diffusion coefficients available in the literature. After that, the chemical diffusion coefficients as a function of compositions and crystal orientations are model predicted and utilized to validate the available experimental/theoretical data with large discrepancies. The result indicates that the ratio of D Li self-ab /D Li self-c should be on the order of 100. Moreover, the analytical modeling of phase transition from O3 to O3′ phase under different charging currents and crystal anisotropies is performed, from which the quantitative atomic mobility−anisotropy−charging current relationships are established. Finally, the battery performance during the charging process is optimized in terms of kinetic requirements, and the optimal charging current (7.5−12.5 mA) and anisotropy orientation angle (close to 0) range corresponding to the preferred battery performance is designed. It is anticipated that this work may serve as a general guide to optimize the battery performance of cathodes during the charging process in Li battery in terms of diffusion kinetics.

In this paper, a parametric three-dimensional (3D) phase-field study of the physical vapor deposition process of metal thin films was performed aiming at quantitative simulations. The effect of deposition rate and model parameters on the microstructure of deposited thin films was investigated based on more than 200 sets of 3D phase-field simulations, and a quantitative relationship between the deposition rate and model parameters was established. After that, the heat maps corresponding to the experimental atomic force microscopy images were plotted for characterization of the surface roughness. Different roughness parameters including the arithmetic average roughness (Ra), root mean square roughness (Rq), skewness (Rsk), and kurtosis (Rku), as well as the ratio of Rq to Ra were calculated and carefully analyzed. A quantitative relationship between the surface roughness and the deposition rate and model parameters was obtained. Moreover, the calculated Rq to Ra ratios for the thin films at the deposition rates of 0.22 and 1.0 nm s−1 agreed very well with the experimental data of the deposited Mo and Ti thin films. Finally, further discussion about the correlative behaviors between the surface roughness and the density was proposed for reasoning the shadowing effect as well as the formation of voids during the thin film production.