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In this work, a nano TiO2-FA/balsa wood-based composites were successfully fabricated by mechanical stirring assisted vacuum impregnation method, and the influence of different impregnation pressures on the microstructure, nanomechanical characteristics and photocatalytic performance of obtained composites were investigated. Results show that thenano TiO2-FA compound modifier was impregnated in the tracheid and attached to thewood cell walls. SEM revealed that the size of TiO2nanoparticles grow larger as theimpregnation pressure increases, and the presence of TiO2globules with some areas agglomerated on the wood cell wall surface. Compared with the unmodified wood, the elastic modulus of cell walls fornano TiO2-FA/balsa wood composites prepared under 0.45 MPa significantly increased by 160.5%, and the hardness improved from 0.36 ± 0.04 GPa to 0.84±0.08 GPa. Furthermore, the UV-Vis showed that the composite exhibited a high removal rate of methylene blue (10 mg.L-1), up to 88.74% within 240 min.

Methylamine iodide based chalcogenide (CH3NH3PbI3) perovskite is a new material of wide interest in the photovoltaic field because of its high conversion efficiency. However, it contains Pb, a heavy metal element, and its structure is not very stable, therefore researchers continue to explore its replacement. It has been found that CH3NH3GeI3 has similar excellent photoelectric properties to CH3NH3PbI3, but there are few literatures on its mechanical properties. In this paper, the mechanical properties of CH3NH3GeI3 are studied by first-principles to provide theoretical guidance for its experimental research and practical application. The results show that under high pressure, the T-phase transforms into C- and O- phases at 0.05 GPa and 0.10 GPa, respectively, and in addition, the Young's modulus E of the O-phase keeps decreasing with increasing pressure, and its Platts ductility index (G/B) is always greater than 0.57, while the T-phase always stays below 0.57, which proves that the T-phase is brittle and the O-phase is ductile. Mechanical stability conditions are met for all three phases as the pressure increases.

Data Availability: Data will be made available on request. Lignocellulosic material is a natural renewable resource and can provide great potential in bioconversion and bioenergy production. This work studied the bioconversion processes of Pinus yunnanensis with white and brown rot fungi treatment, namely T. versicolor, G. trabeum and R. placenta, aiming to clarify the mechanism of enzymatic process and fungi’s intrinsic selectivity in fungal pretreatment during various conversion stages. The results showed that fungi achieved the decomposition and conversion of biomass through the generation of enzymes as well as their action within wood. White rot fungus T. versicolor caused simultaneous rot, which the bioconversion of wood main components occurred uniformly. Brown rot fungi exhibited the ability to depolymerize carbohydrate but degraded polysaccharides with their own bioconversion pathway, and as such caused different conversion of wood chemical components. Morphology observation proved that both white and brown rot fungal pretreatments increased the porosity and improved the accessibility of wood cells. Three kinds of fungi possess the ability to improve the digestibility, but with various situations of the substrate loss. In addition, these three fungi presented their promising potentials in different aspects as well. The research outcomes could provide insight into the mechanism of enzymatic process and role of fungal selectivity on Pinus yunnanensis bioconversion as well as the potential application of fungal pretreatment in future biorefineries and biochemical productions. Regional Project of National Natural Science Foundation of China (31860186, 32260362, 31360157); Joint project of Yunnan Agricultural Basic Research (202101BD070001-058); 111 Project (D21027).

Chicken feather is employed as a source of protein and combined with copper and boron salts to prepare chicken feather protein-based wood preservatives (CFP-WP). The treatability, leachability, chemical structure, crystallinity, thermal properties, micromorphology and decay resistance against fungi of treated wood samples are investigated to explore the efficacy and working mechanisms. The results showed that CFP-WP could penetrate into the wood structure, and NMR analysis indicated the small molecule amino acids hydrolyzed from chicken feather could successfully penetrate into wood. Furthermore, results of FT-IR, XRD, TGA/DTG analysis showed that the active ingredients of preservatives could interact with wood constituents, and CFP-WP were well fixed onto wood blocks. The morphology analysis and decay experiments verified that CFP-WP could protect wood against decay fungi efficiently and prolong the wood service life in consequence. The excellent functionalities of CFP-WP suggests that this eco-formulation could offer great potential to be used as environmentally benign wood preservatives with a more competitive cost.

The inhibition effect of amphoteric surfactant of octadecyl dimethyl betaine (BS-18) on cold rolled steel (CRS) in H3PO4 solution was studied by weight loss, electrochemical technique, surface analysis and quantum chemical calculations. The results show that BS-18 acts as an efficient inhibitor on CRS in 1.0 M H3PO4 medium at 20-50 oC, and the maximum inhibition efficiency is 87.1% with 50 mg L-1 at 20 oC. Its adsorption on steel surface obeys Langmuir adsorption isotherm, which is endothermic process accompanying with the increase of entropy. Compared with uninhibited solution, apparent activation energy, pre-exponential factor, activation enthalpy and activation entropy become higher in inhibited solution, while both reaction constant and rate constant decrease after adding BS-18. Inhibition performance remains more stable from 3 to 48 h, and fluctuates slightly with the acid concentration from 0.5 to 5.0 M. BS-18 is a mixed-type inhibitor through "geometric blocking effect". EIS is a time constant with one depressed capacitive loop in Nyquist plot and one phase angle in Bode phase plot, and the charge transfer resistance turns to become more larger in the presence of BS-18. SEM and AFM micrographs of inhibited CRS surface appear little corrosion, and its contact angle is increased. There are functional groups of C-N and C-N+ in the adsorptive film of BS-18 on CRS surface using XPS analysis. Critical micelle concentration (CMC) of BS-18 is about 20 mg L-1 from surface tension measurements. Quantum chemical calculations confirm that the active adsorption site of BS-18 is the hydrophilic group of N+ and -CH2COO-.

Starch is one of the richest natural polymers with low-cost, non-toxic and biodegradable, but is seldom directly used as corrosion inhibitor due to its poor inhibitive ability and low water solubility. To solve this problem, cassava starch-acryl amide graft copolymer (CS-AAGC) was prepared through grafting acryl amide (AA) with cassava starch (CS), and it was firstly examined as an efficient inhibitor for 1060 aluminum in 1.0 mol·L−1 H3PO4 media. The adsorption behavior of CS-AAGC and its electrochemical mechanism were investigated by weight loss and electrochemical methods. Additionally, the inhibited aluminum surface was fully characterized by a series of SEM, AFM, contact angle measurements and XPS. Results confirm that CS-AAGC performs better inhibitive ability than CS, AA or CS/AA mixture, and the maximum inhibition efficiency of 1.0 g·L−1 CS-AAGC is 90.6% at 20 °C. CS-AAGC acts as a mixed-type inhibitor while mainly retards the anodic reaction. EIS has three time constants, and the polarization resistance is significantly increased in the presence of CS-AAGC. The micrograph of inhibited aluminum surface is of hydrophobic nature with low surface roughness and little corrosion degree.

Scented tea, also known as fragrant tea, mainly comprises green tea as the tea base and the dried and processed flowers of various plants. It is a unique reprocessed tea in China. There are many types of scented tea, including jasmine, lily, osmanthus, rose and honeysuckle. The scenting process greatly influences the quality of the scented tea. Humidifying continuous scenting processes, frying flower processes and innovative drying methods have been developed to resolve the issues of cumbersome, time-consuming and low utilisation rates of flowers in the process of making scented tea. The main chemical components of scented tea are polyphenols as well as exogenous plant glycosides, flavonoids, lactones, coumarins, quercetin, steroids, terpenoids and other compounds. Scented tea plays an active role in the prevention and treatment of various diseases and has as anti-oxidant, anti-cancer, hypoglycaemic, hypolipidemic, immunomodulatory and neuromodulatory effects. This chapter mainly reviews and summarises the types of scented teas and their related health functions.

The inhibition effect of rare earth salt of Ce(SO4)2 on the corrosion of cold rolled steel (CRS) in 0.50 M citric acid (H3C6H5O7) solution was studied by weight loss, electrochemical technique and surface analysis methods for the first time. The results reveal that Ce(SO4)2 behaves as an efficient inhibitor, and the maximum inhibition efficiency reaches a pleasant value of 97.2% at 20 °C with a little concentration of 0.25 mM. The adsorption of Ce(SO4)2 on CRS surface completely obeys Langmuir adsorption isotherm at 20 - 50°C. Ce(SO4)2 is arranged as a mixed-type inhibitor while mainly retards the cathodic reaction. Electrochemical impedance spectroscopy (EIS) has two time constants. Nyquist diagram contains a depressed capacitive loop at high frequencies followed by an inductive loop at low frequencies. The inhibition of CRS surface by Ce(SO4)2 is evidenced through scanning electron microscope (SEM), atomic force microscope (AFM) and confocal laser scanning microscope (CLSM). The inhibitive mechanism can be mainly attributed to the complexes of cerium (IV) ion with citric anions.

The present work successfully fabricated high nonlinear TiO2 varistor ceramics by co-doping with Ge and GeO2, HIP sintering and annealing in nitrogen. Further, its high nonlinear mechanism is investigated. XRD, XPS, SEM-EDAX and SEM analyses demonstrated that annealing can cause acceptor ions segregate to grain boundaries, which increases the acceptor state density, the potential barrier height ΦB and the nonlinear coefficient α. Annealing in nitrogen prevents GeO as the product of Ge and GeO2 in sintering from being oxidized, which is more beneficial to increasing ΦB and α. Increasing the potential barrier height can reduce the background current, thus the leakage current JL reduces. The excess GeO2 dissolving in TiO2 lattice improves the semi-conducting degree of grains, thus EB decreases. In addition, HIP sintering, as well as adding Ge and GeO2 as sintering aids, reduces the sintering temperature. The optimal sintering temperature is 1200 °C. As the doping contents of donor Nb2O5 and acceptor Y2O3 are 0.25 mol%, respectively, the optimum doping contents of 0.15 mol% Ge and 0.45 mol% GeO2 and annealing in nitrogen at 800 °C for 3 h cause the highest ΦB (1.57 eV) and α (14.5), lower EB (11.6 V mm−1) and JL (9.6μA cm−2). TiO2–Nb2O5–Y2O3–Ge-GeO2 ceramics have excellent varistor properties.

The synergistic inhibition effect of walnut green husk extract (WGHE) and sodium lignosulfonate (SLS) on the corrosion of cold rolled steel (CRS) in 3.0 M H3PO4 solution was firstly studied by weight loss, electrochemical technique, surface analysis, quantum chemical calculation and molecular dynamics (MD) simulation. Results show that WGHE acts as a moderate inhibitor with a maximum inhibition efficiency of 73.4%, while SLS is poor inhibitor with the maximum inhibition below 40%. Mixing WGHE with SLS produces strong synergistic inhibition effect, and can significantly improve the inhibitive performance with a pleasant maximum inhibition efficiency of 97.2%. The synergism parameter is high than unity, and increases with the inhibitor concentration, but decreases with an increase of temperature. The adsorption of WGHE, SLS or WGHE/SLS obeys Langmuir adsorption isotherm. Individual WGHE or SLS mainly retards cathodic reaction, while WGHE/SLS mixture drastically inhibits both anodic and cathodic reactions simultaneously. The charge transfer resistance is drastically increased for the WGHE/SLS mixture, but the double electric capacitance decreases to more extent. The inhibited CRS surface by WGHE/SLS clearly appears little corrosion from SEM graph, and is of hydrophobic nature with an obtuse contact angle. Two components of naphthoquinone and 2-phenylchromone in WGHE exhibit synergistic inhibition with SLS. Quantum chemical calculations are well accordance with the expected inhibition order of WGHE/SLS > WGHE > SLS. The WGHE/SLS hybrid co-adsorb on Fe (001) and Fe (110) surfaces in the nearly flat manner, and the adsorption energy is more negative comparing with individual WGHE or SLS.

Cassava starch ternary graft copolymer of cassava starch-sodium allylsulfonate-acryl amide graft copolymer (CS-SAS-AAGC) was synthesized through cassava starch (CS) chemically modified by grafting two monomers of sodium allylsulfonate (SAS) and acryl amide (AA) simultaneously. The inhibition performance of CS-SAS-AAGC on cold rolled steel (CRS) in 1.0 M HCl solution was experimentally studied by weight loss, electrochemical techniques and surface analysis, and its adsorption was theoretically investigated by both quantum chemical calculation and molecular dynamic (MD) simulation. The results indicate that CS-SAS-AAGC shows an optimum inhibition efficiency as high as 97.2% at 50 mg L−1, and its inhibitive ability exhibits more stronger than that of CS, SAS or AA. CS-SAS-AAGC behaves as a mixed-type inhibitor through geometric blocking effect. SEM and AFM images clearly reveal that the corrosion of CRS surface is efficiently retarded by CS-SAS-AAGC. Contact angle result suggests that the inhibited CRS surface is of hydrophobic nature. The adsorption active sites of CS-SAS-AAGC are mainly the grafted monomers of SAS and AA. Keywords: Corrosion inhibitor, Hydrochloric acid, Steel, Ternary graft copolymer, Adsorption

In this work, a novel Cu–UiO-66/wood composite was successfully fabricated by a facile in situ growth strategy, and the influence of Cu–UiO-66 metal-organic framework (MOF) loading on the wood substrate thermal stability and flame retardancy were investigated. Scanning electron microscopy images indicated that the octahedral Cu–UiO-66 microparticles were uniformly and firmly decorated on the lumen surface within the balsa wood scaffold. The incorporation of only 6.5 wt% Cu–UiO-66 MOF remarkably enhanced the thermal stability and flame retardancy of the natural wood. Compared with the untreated wood, the peak heat release rate of the Cu–UiO-66/wood composite exhibited a drastic decline by 73.1% from 94.5 to 25.4 W·g−1 and the total heat release from 7.7 to 5 kJ·g−1. Meanwhile, the treated wood had a strong self-extinguishing ability and the char residue rate of the Cu–UiO-66/wood is significantly increased by 132.7%. Therefore, this work provided an effective means of achieving the fire safety wood via introducing and constructing Cu–UiO-66 MOF flame retardants material.

To prepare a natural tannin-based adhesive with good water resistance, an environment friendly furfuryl alcohol-glyoxal resin (FG) synthesized in the laboratory was developed as a cross-linker for tannin-based adhesives. 13C Nuclear Magnetic Resonance (NMR) and Matrix-Assisted Laser Desorption-Ionization Time-of-Flight (MALDI-TOF) mass spectroscopy results indicated that furfuryl alcohol and glyoxal reacted under acidic conditions and that the -CH-(OH)- groups could be shown to be the ones involved in the cross-linking of the tannin-furfuryl-glyoxal adhesive (TFG). The results for the wet shear strength of TFG-bonded plywood showed that the cured TFG was improved and better than that bonded with a tannin-furfuryl alcohol (TF) adhesive. Moreover, the TFG adhesive cross-linked with 12% epoxy resin (EPR) presented a good water resistance. It had a modulus of elasticity (MOE) higher than that of tannin-furfuryl alcohol-formaldehyde (TFF), TF and phenol-formaldehyde (PF) adhesives.

The inhibition effect of triazolyl blue tetrazolium bromide (TBTB) on cold rolled steel (CRS) in three chlorinated acetic acids of monochloroacetic acid (ClCH2COOH), dichloroacetic acid (Cl2CHCOOH) and trichloroacetic acid (Cl3CCOOH) was studied by weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) methods. Meanwhile, the adsorption mechanism of TBT+ (organic part of TBTB) was theoretically investigated by quantum chemical calculation and molecular dynamics (MD) simulations. The results show that TBTB acts as a good inhibitor, and inhibition efficiency in three chlorinated acetic acids follows the order: ClCH2COOH

The corrosion inhibition of cold rolled steel (CRS) in 7.0 mol·L− 1 H2SO4 solution by red tetrazolium (RTZ) was carefully investigated using both experimental procedures and theoretical techniques. The results show that RTZ acts as an effective inhibitor for the corrosion of CRS in 7.0 mol·L− 1 H2SO4, and the maximum inhibition efficiency is higher than 95% with a RTZ concentration of 2.0 mmol·L− 1. The adsorption of RTZ on CRS surface follows Langmuir isotherm. RTZ effectively retards both cathodic and anodic reactions, and acts as a mixed-type inhibitor. EIS exhibits two capacitive loops, and their resistances increase drastically in the presence of RTZ. SEM and AFM confirm that the addition of RTZ could significantly retard the corrosion of CRS surface. A series of characterizations like FTIR, RS, XRD and XPS reveal that the corrosion CRS surface is composed of the corrosion products of iron sulfates, iron oxides and iron hydroxide, as well as inhibitor. Theoretical results of quantum chemical calculation and molecular dynamics (MD) indicate that the adsorption center of RTZ+ (organic cationic part of RTZ) mainly relies on its tetrazole ring, and the adsorption of RTZ+ on Fe (001) surface is in a nearly flat orientation mode.

Cassava starch-sodium allylsulfonate-acryl amide graft copolymer (CS-SAS-AAGC) was prepared by in situ polymerization of sodium allylsulfonate (SAS) and acryl amide (AA) in the presence of cassava starch (CS). The inhibition performance was tested by immersing aluminum in HCl solution using weight loss and electrochemical methods. CS-SAS-AAGC showed an inhibition efficiency as high as 95% at low inhibitor concentration of 100 mg/L. The inhibitive performance is much higher than that of CS, SAS, AA, CS/AA, CS/SAS or CS/AA/SAS mixture. The adsorption of CS-SAS-AAGC on aluminum surface was found to obey Langmuir adsorption isotherm. CS-SAS-AAGC behaves as a mixing-type inhibitor, while mainly inhibiting the cathodic reaction. Electrochemical impedance spectroscopy (EIS) has two time constants with a large capacitive loop at high frequencies followed by also a large inductive one at low frequencies. The inhibition of aluminum surface by CS-SAS-AAGC is evidenced through scanning electron microscope (SEM) and contact angle images. The adsorption mechanism was theoretically analyzed by quantum chemical calculation and molecular dynamic (MD) simulation.

Mikania micrantha extract (MME) was prepared by reflux extraction method with 40% C2H5OH water solution. The synergistic inhibition effect of MME and potassium iodide (KI) on cold rolled steel (CRS) in 0.50 M H2SO4 solution was studied by weight loss and electrochemical methods for the first time. The CRS surfaces were fully characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). Meanwhile, the main effective compounds in MME were discussed in depth by high performance liquid chromatography (HPLC). The results show that either MME or KI acts as a moderate inhibitor on CRS in 0.50 M H2SO4 solution, and the maximum inhibition efficiency is below 80%. The mixture of MME/KI has a pleasant inhibition performance with the maximum inhibition efficiency of 94.4%. There is an evident synergistic effect between MME and KI, and the corresponding synergism parameter is higher than 1. Regardless of the extra addition of KI, the adsorption of MME obeys the Langmuir adsorption isotherm. The presence of KI enhances the adsorption of MME owing to larger value of adsorption equilibrium constant for MME/KI mixture. MME is a cathodic inhibitor, while MME/KI can be arranged as a mixed-type inhibitor, and the inhibition of both cathodic and anodic reactions is further enhanced by the MME/KI combination. Nyquist diagram mainly exhibits a capacitor loop that is controlled primarily by charge transfer. As the concentration of corrosion inhibitor increases the capacitance arc length gradually increases, especially for MME/KI mixture. The charge transfer resistance increases more than 10 times and shows excellent corrosion inhibition. SEM and AFM clearly confirm that the presence of MME/KI has a significant effect on inhibiting the corrosion of CRS, and the inhibition is expected to follow the order: MME/KI > KI > MME. XPS reveals that the MME/KI mixture can adsorb on steel surface to achieve inhibitive film. Most important, there is also a synergistic inhibition of effective components in MME (chlorogenic acid, ferulic acid) with KI.

The inhibition effect of five pyrimidine derivatives (2-chloropyrimidine, 2-hydroxypyrimidine, 2-bromopyrimidine, 2-aminopyrimidine, 2-mercaptopyrimidine) on the corrosion of cold rolled steel (CRS) in 0.1 M HNO 3 solution was comparatively examined. 2-Mercaptopyrimidine (MP) was found to be an effective inhibitor with the inhibition efficiency as high as 99.1% at a low concentration 0.50 mM. But other four pyrimidine derivatives exhibited poor inhibitive ability. The addition of MP caused both anodic and cathodic curves to low current densities, and was found to significantly strengthen the impedance. Quantum chemical calculation and molecular dynamic simulation were performed to theoretically investigate the adsorption mechanism.

The synergistic inhibition effect of 5-aminotetrazole (AT) and 4,6-dihydroxypyrimidine (DHP) on the corrosion of cold rolled steel (CRS) in H 3 PO 4 solution was studied by weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS), scanning electron microscope (SEM), quantum chemical calculation and molecular dynamics (MD) methods. The results show that AT exhibits a moderate inhibitive effect, and DHP has a poor effect. However, incorporation AT with DHP significantly improves the inhibitive performance, and yields synergism. The adsorption of AT in the absence and presence of DHP obeys Langmuir adsorption isotherm. AT/DHP mixture acts as a mixed-type inhibitor. The combined AT and DHP molecules co-adsorb on the Fe (001) surface in the nearly flat manner, and the adsorption energy is larger than individual AT or DHP.

Cassava starch graft copolymer (CSGC) was prepared by grafting acryl amide (AA) onto cassava starch (CS). The inhibition effect of CSGC on the corrosion of cold rolled steel (CRS) in 1.0M H2SO4 solution was first studied by weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscope (SEM) methods. The results show that CSGC is a good inhibitor, and inhibition efficiency of CSGC is higher than that of CS or AA. The adsorption of CSGC on steel surface obeys Langmuir adsorption isotherm. CSGC is a mixed-type inhibitor at 20 °C, while mainly a cathodic inhibitor at 50 °C.

The inhibition effect of two mercaptopyrimidine derivatives of 4-amino-6-hydroxy-2-mercaptopyrimidine (AHMP) and 4,6-dihydroxy-2-mercaptopyrimidine (DHMP) on cold rolled steel (CRS) in HCl solution was studied by weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS), scanning electron microscope (SEM), quantum chemical calculation and molecular dynamics (MD) simulations methods. The results show that both mercaptopyrimidine derivatives act as good inhibitors, and inhibition efficiency follows the order: AHMP > DHMP. The adsorption of either inhibitor on steel surface obeys Langmuir adsorption isotherm. Two mercaptopyrimidine derivatives are mixed-type inhibitors. The inhibitor molecules adsorb on the Fe (0 0 1) surface in the nearly flat manner.