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PurposeClimate change increases systematic risk for firms, especially those in the agricultural industry. Therefore, the need to examine the consequences of climate-related risks on agribusiness companies' financial performance across the globe and emerging markets has risen. In this context, the paper aims to investigate the effects of climate change risks on the financial performance of agriculture listed firms in Vietnam.Design/methodology/approachThe study sample includes 77 Vietnamese listed firms in the agricultural industry in the period of 2015–2019. The authors chose temperature, wind, rainfall and humidity proxies to measure climate change. The OLS regression, random regression and sub-sample analysis have been used to examine the impacts of climate risks on firms' financial performance.FindingsEmpirical results show that rain and temperature have positive impacts on financial performance of Vietnamese agriculture listed firms, while wind and humidity have insignificant impacts on financial performance.Research limitations/implicationsThe research helps researchers, businesses, practitioners and policymakers interested in the agricultural industry, especially those in developing and emerging countries, to develop a deep understanding of the impact of climate change risks on firm performance and therefrom prepare necessary measures to reduce the negative impacts.Originality/valueThis study adds to the literature stream on the impacts of climate change on financial performance. It is the first study to investigate this impact in Vietnam, a country which depends mainly on agriculture.

This survey studies the current status of the informational text writing competence of Philological Pedagogy students in Vietnam. In order to have a complete and comprehensive view of the literacy competence of Philology Pedagogy students, we have surveyed 366 students of 11 Philology Pedagogy Universities in Vietnam. The survey questions focused on a number of issues such as students' perceptions of informational texts and their role in learning and living, informational writing skills, and awareness of factors affecting informational writing skills, and teaching methods of informational writing skills. This study uses survey methods, analytical - synthesis methods, descriptive methods, etc. The survey results are the basis for us to design teaching methods of informational text writing effectively. At the same time, it is also the basis for us to propose changes in the curriculum for students of Philology Pedagogy, in which it is imperative to focus on testing, assessing writing competence in general, and informational text writing competence in particular.

In this work, we proposed a facile approach to fabricate a superhydrophobic surface for anti-icing performance in terms of adhesive strength and freezing time. A hierarchical structure was generated on as-received Al plates using a wet etching method and followed with a low energy chemical compound coating. Surfaces after treatment exhibited the great water repellent properties with a high contact angle and extremely low sliding angle. An anti-icing investigation was carried out by using a custom-built apparatus and demonstrated the expected low adhesion and freezing time for icephobic applications. In addition, we proposed a model for calculating the freezing time. The experimented results were compared with theoretical calculation and demonstrated the good agreement, illustrating the importance of theoretical contribution in design icephobic surfaces. Therefore, this study provides a guideline for the understanding of icing phenomena and designing of icephobic surfaces.

In this work, we proposed a facile approach to fabricate a superhydrophobic surface for anti-icing performance in terms of adhesive strength and freezing time. A hierarchical structure was generated on as-received Al plates using a wet etching method and followed with a low energy chemical compound coating. Surfaces after treatment exhibited the great water repellent properties with a high contact angle and extremely low sliding angle. An anti-icing investigation was carried out by using a custom-built apparatus and demonstrated the expected low adhesion and freezing time for icephobic applications. In addition, we proposed a model for calculating the freezing time. The experimented results were compared with theoretical calculation and demonstrated the good agreement, illustrating the importance of theoretical contribution in design icephobic surfaces. Therefore, this study provides a guideline for the understanding of icing phenomena and designing of icephobic surfaces.

Novel approach to fabricate In2O3 nanocrystal (NC)–π conjugated molecule 4,4′-ethyne-1,2-diyldibenzoic acid (EBA) hybrid materials by ligand exchange process, Sonogashira coupling reaction, and their utility as a lithium ion battery anode material have been developed. Here, discharge capacity of 900 mAh g−1, excellent rate performance under ultrahigh current density of 20 C, and initial Coulombic efficiency of 60% at moderate charging/discharging current density of 5 C after 100 cycles have been demonstrated, which are synergistically capable of overcoming the drawback of previous In2O3 material. The π–π network allows fast electron/Li+ transport and significant decrease in interfacial resistance in charge/discharge state.

The increasing interest in powerful biological activity of plant phenolics and flavonoids outlined the necessity of determining their contents in vegetables. The study comprised 10 vegetable species commonly consumed in Hue. The total phenolic content was determined by using the Folin-Ciocalteu assay. The content of total flavonoids was measured also spectrophotometrically by using the aluminum chloride colorimetric assay. Antioxidant activity of extracts were expressed as IC50 values (µg/ml). Values in IC50 ranged from 2.08 to 51.06. The total phenolic content ranged from 3.18 ± 0.03 to 11.87 ± 0.06 (mg/g) of dry weight of extract expressed as gallic acid equivalents. The total flavonoid concentrations varied from 2.33 ± 0.03 to 19.47 ± 0.21 (mg/g), expressed as quercetin equivalents.

In order to pioneer the electron transport properties of silicon (Si) quantum dot-molecule hybrid polymers, we investigate the electron transport properties of the benzene molecule in silicon (Si) semiconductor electrodes, based on nonequilibrium Green's function (NEGF) method coupled with density functional theory (DFT), in comparison with conventional gold (Au) metal electrodes, with three different anchoring linker groups: thiol for dithiol-benzene (DTB), methylene for dimethyl-benzene (DMB), and direct bonding for benzene (Ph). It is interestingly found that, due to band gap nature of the Si semiconductor electrodes, the molecular junctions with the Si electrodes show no current up to the bias voltage of around 0.8 V. In addition, the DTB molecular junctions in the Si semiconductor electrodes connected with Si–S bond show higher conducting properties than other DMB and Ph molecular junctions directly coupled to the electrodes with the Si–C bonds (DMB

We developed a new class of organic surface ligands; 2-aminopyridine (2AP), 4-aminobenzoic acid (4ABA), and benzoic acid (BA); for use in the solution ligand exchange of nanocrystals (NCs) in the presence of nitric acid (HNO3). Here, colloidal NCs synthesis is used for the first time. These short, air-stable, easy-to-model ligands bind to the surface of the indium oxide nanocrystal (In2O3 NC) and provide the electrostatic stabilization of NC semiconductor dispersions in N,N-dimethylformamide, allowing for a solution-based deposition of NCs into thin-film transitors (TFTs). The shorter organic ligands greatly facilitate electronic coupling between the NCs. For example, thin films made from 2AP-capped In2O3 NCs exhibited a high electron mobility of μ≈9.5 cm2/(V·s), an on-off current ratio of about10(7), and a subthreshold swing of 2.34 V/decade. As the ligand length decreased, the electron mobility increased exponentially. Furthermore, we also report on the temperature-dependent behavior of the electron transport of In2O3 NCs films, in the case in which thin films were cured at 150 °C, as the 2AP, BA, and 4ABA ligand molecules were sustained on the NC. We demonstrated a hopping transport mechanism instead of a band-like transport, and the thermally activated carrier transport process governed the charge transport in our In2O3 NC thin-film solid.

NCs) with sizes of 5.5 nm–10 nm were synthesized by hot injection of themixture precursors, indium acetate and oleic acid, into alcohol solution (1-octadecanol and 1-octadecencemixture). Field emission transmission electron microscopy (FE-TEM), High resolution X-Ray diffraction (X-ray), Nuclear magnetic resonance (NMR), and Fourier transform infrared spectroscopy (FT–IR) wereemployed to investigate the size, surface molecular structure, and crystallinity of the synthesized In

Indium-doped zinc oxide nanocrystals (IZO NCs), capped with stearic acid (SA) of different sizes, were synthesized using a hot injection method in a noncoordinating solvent 1-octadecene (ODE). The ligand exchange process was employed to modify the surface of IZO NCs by replacing the longer-chain ligand of stearic acid with the shorter-chain ligand of butylamine (BA). It should be noted that the ligand-exchange percentage was observed to be 75%. The change of particle size, morphology, and crystal structures were obtained using a field emission scanning electron microscope (FE-SEM) and X-ray diffraction pattern results. In our study, the 5 nm and 10 nm IZO NCs capped with stearic acid (SA-IZO) were ligand-exchanged with butylamine (BA), and were then spin-coated on a thermal oxide (SiO2) gate insulator to fabricate a thin film transistor (TFT) device. The films were then annealed at various temperatures: 350 °C, 400 °C, 500 °C, and 600 °C. All samples showed semiconducting behavior and exhibited n-channel TFT. Curing temperature dependent on mobility was observed. Interestingly, mobility decreases with the increasing size of NCs from 5 to 10 nm. Miller-Abrahams hopping formalism was employed to explain the hopping mechanism insight our IZO NC films. By focusing on the effect of size, different curing temperatures, electron coupling, tunneling rate, and inter-NC separation, we found that the decrease in electron mobility for larger NCs was due to smaller electronic coupling.

Barium titanate nanocrystals (BT NCs) were prepared under solvothermal conditions at 200 °C for 24 h. The shape of the BT NCs was tuned from nanodot to nanocube upon changing the polarity of the alcohol solvent, varying the nanosize in the range of 14-22 nm. Oleic acid-passivated NCs showed good solubility in a nonpolar solvent. The effect of size and shape of the BT NCs on the ferroelectric properties was also studied. The maximum polarization value of 7.2 μC/cm(2) was obtained for the BT-5 NC thin film. Dielectric measurements of the films showed comparable dielectric constant values of BT NCs over 1-100 kHz without significant loss. Furthermore, the bottom gate In2O3 NC thin film transistors exhibited outstanding device performance with a field-effect mobility of 11.1 cm(2) V(-1) s(-1) at a low applied gate voltage with BT-5 NC/SiO2 as the gate dielectric. The low-density trapped state was observed at the interface between the In2O3 NC semiconductor and the BT-5 NCs/SiO2 dielectric film. Furthermore, compensation of the applied gate field by an electric dipole-induced dipole field within the BT-5 NC film was also observed.

This paper investigates empirically the relationship between firm size and production efficiency, and the relationship between firm size and the likelihood of paying bribes using firm-level data from Vietnam. Our analysis indicates that middle-sized firms’ production efficiencies tend to be lower than small-sized or large-sized firms in most of the manufacturing industries, and as firm size increases, the likelihood of paying bribes also increases. Firm size distribution has been a particular concern of economists for almost a century, and more recently, there has been increasing interest in the firm size distribution of developing nations, particularly the missing middle phenomenon, which refers to the fact that the distribution of firm size in developing countries tends to be bimodal. Our empirical results shed light on the relationship between firm size, production and corruption, and provide insights into these relations.