Volume 16 Issue 3

Surface properties include both surface roughness and friction. With a stylus-type contact method, it is necessary to obtain either a surface roughness profile or a friction profile that is affected by stylus shape and size, its contact force on the sample, the scan speed, and the data acquisition rate. As a new surface parameter, the mean absolute deviation (MAD) from an average property has been introduced. It represents the deviation from either the roughness average (Ra) and the average coefficient of friction (COF), respectively. While Ra or average COF depends on the instrument and its operating conditions, the MAD should not depend on them because it represents the variations within the sample.

Two survey instruments measuring undergraduate students’ beliefs about bioproducts/bioenergy and related careers were developed and validated in this research study. The Beliefs about Bioproducts/Bioenergy (BABB) and Career Interest in Bioproducts/Bioenergy (CIBB) surveys were administered to undergraduate students enrolled in courses in a natural resources college. BABB (N = 168) and CIBB (N = 203) survey results were analyzed using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Validity and reliability were demonstrated. The BABB has two related scales, Personal (P) and Societal (S), which can be used together or separately. ANOVA and t-test analyses determined that students with majors closely related to bioproducts/bioenergy held significantly more positive personal and societal beliefs about bioproducts/bioenergy, as well as related career interests. Differences were identified based on gender, but not by race/ethnicity. Measuring student beliefs about bioproducts/bioenergy and interest in related careers may help to gauge trends and changes in beliefs that influence environmentally-related choices and support efforts to prepare a diverse workforce for the bioeconomy. The authors recommend the use of these surveys to measure the impacts of academic and professional development experiences.

The chemical composition of hardwoods sawdust and citrus residues from four states of the Mexican Republic (Quintana Roo, Durango, Veracruz, and Sonora) were determined. The results ranged as follows: total extractives from 8.2% (Quercus spp.) to 35.0% (lime leaves), holocellulose from 45.4% (lime leaves) to 70.6% (Lysiloma latisiliquum), lignin from 3.9% (lemon peels) at 25.4% (Caesalpinia platyloba), ash from 0.4% (orange branches) to 6.3% (lemon peels), pH from 5.1 (Swartzia cubensis) to 7.3 (orange branches), and calorific value of 19.8 MJ/kg (Lysiloma latisiliquum and Quercus spp.) to 21.7 MJ/kg (Olneya tesota). With the exception of the oak samples, in all the biomass samples the extractives content is relatively high (10.1% for Lysiloma latisiliquum to 35% for Persian lime leaves), and could represent a potential for future study and applications in the field of antioxidants. Due to the chemical properties and calorific value, the biomass samples studied present potential for local use as densified biofuels (pellets or briquettes).

A multi-directional relationship may be conceivable between elements and melatonin in sessile organisms. Melatonin is an important hormone that helps regulate metabolism. This study investigated how different doses (0 μM/control, 250 μM, 500 μM, 1000 μM, and 1500 μM) of exogenous melatonin supplementations (EMS) affected the elemental contents in Anatolian black pine (Pinus nigra Arnold. ssp. pallasiana (Lamb.) Holmboe) seedling tissues (root, stem, and needle). Two different application forms (root-dipping and needle-spraying) were selected in the study. In the samples of seedling tissues, sodium (Na), potassium (K), calcium (Ca), iron (Fe), aluminum (Al), magnesium (Mg)/ppm; chrome (Cr), cobalt (Co), copper (Cu), manganese (Mn), nickel (Ni), phosphorus (P), selenium (Se), silicium (Si), silver (Ag), sulfur (S), zinc (Zn), and molybdenum (Mo)/ppb were analyzed using inductively coupled plasma optical emission spectroscopy (ICP-OES). Of the 18 elements examined, there was a statistically significant difference (p<0.05) between all seedling tissues and different doses of EMS. The results show that EMS may have the regulatory effect on seedling tissue element metabolism.

Zanthoxylum schinifolium Sieb. et Zucc. (syn. Fagara schinifolia Engler) was studied for its potential anti-inflammatory properties. The hydrosol extract prepared from the Z. schinifolium branch was analyzed by gas chromatography/mass spectrometry. Here, five main chemical components were identified in the hydrosol of the branches of this shrub. The main chemical compounds in the branch inhibited both an Immunoglobulin E (IgE)-antigen complex and a dinitrophenyl-bovine serum albumin (DNP-BSA)-induced β-hexosaminidase release in a dose-dependent manner in RBL-2H3 mast cells, and at the tested concentrations did not show cytotoxicity to RBL-2H3 cells. Moreover, hydrosol obtained from the branch substantially inhibited a lipopolysaccharide (LPS) induced overproduction of intracellular active oxygen (ROS) and nitric oxide (NO). Consistently, the soluble N-ethylmaleimide-sensitive factor-attachment protein receptor (SNARE) proteins of SNAP23, syntaxin4, VAMP7, and VAMP8 were remarkably decreased through hydrosol treatment. Hydrosol suppressed the activation of SNARE proteins in DNP-BSA-stimulated RBL-2H3 cells and inhibited ROS and NO in LPS-stimulated RAW264.7 cells. Camphor and estragole are the main chemical components of hydrosol and downregulate the LPS-induced phosphorylation of the SNARE proteins. The hydrosol obtained from the branch of Z. schinifolium has therapeutic benefits for allergic inflammatory diseases.

Wood-plastic composites have attracted extensive attention throughout the world because of their advantages. However, the manufacturing mechanism of the wood-plastic composites, i.e., high-speed milling technology, is not perfect and needs further study. The effects of the cutting parameters, i.e., the spindle speed, feed rate, axial milling depth, and radial milling depth, on the surface roughness and chip morphology were studied; the surface roughness values, Ra and Rz of high-speed milling wood-plastic composites samples were measured via high precision surface roughness measuring instrument, and their regression equations were calculated. The chips produced via a high-speed milling process were collected and studied. The results showed that the surface roughness of the wood-plastic composites increases with an increase in the axial depth, feed rate, or radial depth, but decreases with an increase in the spindle speed. In addition, the axial milling depth, feed rate, and spindle speed had a significant effect on the morphology of the chips. However, the effect of the radial milling depth on the morphology of the chips was not obvious. The results can provide a scientific basis for the optimization of high-speed milling processing of wood-plastic composites.

Aniline derivates are widely used in rubber products as anti-aging agents, but their biological toxicity causes harm in the use and recycling of rubber products. Therefore, in this study, a high-performance poly(3,4,5,6-tetra-fluorophthalonitrile-β-cyclodextrin)(P-TFPN-β-CD) solid-phase extraction (SPE) adsorbent was synthesized and applied to extract and detect aniline derivatives in rubber specimens. After crosslinking with 3,4,5,6-tetrafluorophthalonitrile (TFPN), the polymer exhibited mesopores (7.88 nm) and a large specific area (55.2 m2/g). The porous structure significantly improved the extraction efficiency (recovery was between 90.1% and 110.5%) and rate (60% in 10 s) of 4 aniline derivatives (aniline, N-ethyl aniline, 1,2-phenylenediamine, and p-phenylenediamine). With a combined gas chromatographic-flame ionization detector (GC-FID), the extracted aniline derivatives were accurately detected (RSD = 1.60% to 9.90%). Due to the weak interaction between P-TFPN-β-CD and analyte, the prepared poly-TFPN-β-CD SPE adsorbent was regenerated via mild washing with methanol. The high absorption capacities remained after 4 extracting-washing cycles. The novel porous SPE adsorbent showed good extracting and recycling performance for the analysis and detection of aniline compounds in rubber. Thus, it has good prospects for application to improve detection efficiency and reduce cost.

Today’s environmental concerns are pressuring industries to substitute paper-based materials in place of plastics in many sectors including packaging. However, assembling papers and paperboards using environmentally friendly solutions remains a technological challenge. In this context, ultrasonic (US) welding is an alternative to adhesives. In this work, the potential of US welding to assemble folding boxboards was investigated. Folding boxboards are commonly coated to enhance printability. This coating is generally composed of mineral pigments (85 to 90%) and polymer binders (10 to 12%). This study evaluated whether the presence of the coating layer allows the assembly of paperboards by US welding. Results indicated that welding coated folding boxboards is possible provided that coating weight and binder content are high enough. The mechanical performances of the welded boards met the requirements of most packaging applications. Adhesion in the welded joint resulted from a combination of thermoplastic (melting and flowing of the binder) and thermoset (degradation reactions) effects. However, it was not possible to assemble coated folding boxboards without degrading the welding zone. While the materials and process need to be optimized, this work represents a big step forward toward the adhesive-free assembling of paper-based materials.

Cellulose nanocrystals (CNCs) were wet-spun in a coagulation bath for the fabrication of microfilaments, and the effect of sodium alginate (AL) addition on the wet-spinnability and properties of the microcomposite filament was investigated. The CNC suspension exhibited excellent wet-spinnability in calcium chloride (CaCl2) solution, and the addition of AL in CNC suspension resulted in the enhancement of the wet-spinnability of CNCs. As the AL content increased from 3% to 10%, the average diameter of the microcomposite filament decreased, and its tensile properties deteriorated. The increased spinning rate caused an increase in the orientation index of CNCs, resulting in an improvement in the tensile properties of the microcomposite filament.

Despite previous efforts, the fabrication of superhydrophobic substrate via an environment friendly and easy approach remains a great challenge. In this study, a low cost, simple, and green procedure was developed to prepare a superhydrophobic paper surface that is acceptable for the papermaking industry. First, a wax mixture (beeswax & carnauba wax) was emulsified and coated on the filter paper surface. Then, the coated paper was annealed at different temperatures. The further heat-treatment-rendered wax-coated paper hydrophobic or superhydrophobic because submicrometer or micrometer wax structures were present on the paper surface. The water contact angle of the annealed filter paper sample reached 151.5° at 60 °C, and the sliding angle was under 10°. Further, the relationship between surface composition and the hydrophobic properties of the coated paper samples was discussed. The obtained paper samples showed great potential in water/oil separation, as they had an efficiency over 99%. This work proposed a new simple and mild approach to fabricate superhydrophobic filter papers and explored the hydrophobicity and water/oil separation properties.