Bamboo grid versus polyvinyl chloride as packing material in cooling tower: Energy efficiency and environmental impact assessment.

As an abundant and fast-growing biomass, bamboo can be used as construction materials owing to its desirable physical and mechanical properties, environmentally friendly features, and alternative to replace toxic and hazardous wastes in industrial processing. In this study, grid material made from bamboo (termed 'bamboo grid') was developed and compared to commercially used polyvinyl chloride (PVC) as packing material in cooling towers; PVC packing has drawbacks such as fouling, deposit buildup, low durability, and is harmful to environments. The cooling capacity, energy efficiency and environmental impact of bamboo grid packing were evaluated via life cycle assessment (LCA), particularly the cumulative energy demand (CED) and the Building for Environmental and Economic Sustainability (BEES). Although the thermal performance of the PVC packing was found higher than that of the bamboo grid packing, the bamboo grid packing showed improved resistance characteristic, recording a total saving of 529.2 tons of standard coal during a six-month field test in a real thermal power generation plant. LCA results revealed that the utilization of bamboo-grid packing to replace PVC packing in cooling towers reduced total CED from 3420 MJ to 561 MJ per functional unit, achieving 6 times reduction. A desirable reduction ranging from 1.5 to 10.5 times was also recorded for the BEES indices. This LCA comparison analysis confirmed the improvement of energy efficiency and reduction of environmental impact by using the bamboo grid to replace PVC as packing material in cooling towers. The major environmental impact (BEES) indices (e.g., the total Global warming potential, Acidification, Eutrophication and Smog) were reduced by 1.5-10.5 times via the use of bamboo grid. The results demonstrate that bamboo grid packing is a good alternative to replace existing grid packing materials such as concrete and PVC that are harmful to human health and environments.

Nitrogen Self-Doped Activated Carbons Derived from Bamboo Shoots as Adsorbent for Methylene Blue Adsorption.

Bamboo shoots, a promising renewable biomass, mainly consist of carbohydrates and other nitrogen-related compounds, such as proteins, amino acids and nucleotides. In this work, nitrogen self-doped activated carbons derived from bamboo shoots were prepared via a simultaneous carbonization and activation process. The adsorption properties of the prepared samples were evaluated by removing methylene blue from waste water. The factors that affect the adsorption process were examined, including initial concentration, contact time and pH of methylene blue solution. The resulting that BSNC-800-4 performed better in methylene blue removal from waste water, due to its high specific surface area (2270.9 m2 g-1), proper pore size (2.19 nm) and relatively high nitrogen content (1.06%). Its equilibrium data were well fitted to Langmuir isotherm model with a maximum monolayer adsorption capacity of 458 mg g-1 and a removal efficiency of 91.7% at methylene blue concentration of 500 mg L-1. The pseudo-second-order kinetic model could be used to accurately estimate the carbon material's (BSNC-800-4) adsorption process. The adsorption mechanism between methylene blue solution and BSNC-800-4 was controlled by film diffusion. This study provides an alternative way to develop nitrogen self-doped activated carbons to better meet the needs of the adsorption applications.

Tunable and selective hydrogenation of furfural to furfuryl alcohol and cyclopentanone over Pt supported on biomass-derived porous heteroatom doped carbon.

The search for and exploitation of efficient catalytic systems for selective conversion of furfural into various high value-added chemicals remains a huge challenge for green synthesis in the chemical industry. Here, novel Pt nanoparticles supported on bamboo shoot-derived porous heteroatom doped carbon materials were designed as highly active catalysts for controlled hydrogenation of furfural in aqueous media. The porous heteroatom doped carbon supported Pt catalysts were endowed with a large surface area with a hierarchical porous structure, a high content of nitrogen and oxygen functionalities, a high dispersion of the Pt nanoparticles, good water dispersibility and reaction stability. Benefiting from these features, the novel Pt catalysts displayed a high activity and controlled tunable selectivity for furfural hydrogenation to produce furfuryl alcohol and cyclopentanone in water. The product selectivity could be easily modulated by controlling the carbonization temperature of the porous heteroatom doped carbon support and the reaction conditions (temperature and H2 pressure). Under mild conditions (100 °C, 1 MPa H2), furfuryl alcohol was obtained in water with complete conversion of the furfural and an impressive furfuryl alcohol selectivity of >99% in the presence of Pt/NC-BS-500. A higher reaction temperature, in water, favored rearrangement of the furfural (FFA) with Pt/NC-BS-800 as the catalyst, which resulted in a high cyclopentanone yield of >76% at 150 °C and 3 MPa H2. The surface properties and pore structure of the heteroatom doped carbon support, adjusted using the carbonization temperature, might determine the interactions between the Pt nanoparticles, carbon support and catalytic reactants in water, which in turn could have led to a good selectivity control. The effect of different reaction temperatures and reaction times on the product selectivity was also explored. Combined with exploration of the distribution of the reaction products, a reaction mechanism for furfural reduction has been proposed.

Economic analysis of a hypothetical bamboo-biochar plant in Zhejiang province, China.

Significant quantities of bamboo waste are generated in Zhejiang province, China. Many small businesses in this area convert this waste to biochar for use as a cooking fuel (in residential barbecues). This case study was conducted to evaluate the potential economic benefits of building and operating an industrial-sized plant in this province, yielding 500 tonnes per year. The researchers developed a conceptual design for a hypothetical biochar plant and then calculated net present value (NPV), investment payback period (PBP), internal rate of return (IRR), and sensitivity analysis. Results show that the static investment PBP would be 2.58 years, the IRR would be 38.8%, and the NPV would be US$ 486,700. The IRR would be higher than the forestry industry benchmark (11%), indicating that a production line of bamboo-biochar with the stated yield not only could generate higher profits, but also could achieve a better return on investment. Thus, this study indicates that there are good market prospects for the bamboo-biochar industry in this region. The influence of sales prices on the IRR was more than that of operational costs, indicating that a large-scale plant should be designed to produce a high-quality bamboo-biochar. Supply chain issues such as transportation distances between locations where bamboo wastes are generated and the biochar plant should be considered in advance when siting new bamboo-biochar plants. The results from this research provide guidance to those considering development of bamboo-biochar plants in other parts of China.

[Research on Chemical Constituents of Bamboo Fiber Cell Wall Based on Nano-IR Technology].

Nano-IR technology was firstly employed on bamboo fiber research with purpose to further understand the fine structure of bamboo fiber cell wall. Chemical constituent distribution of bamboo fiber was studied, and the feasibility of the novel technology was discussed by comparing with other traditional methods. The results showed that Nano-IR technology, which has made a breakthrough on diffraction limit of traditional infrared spectroscopy, can acquire nano-scale infrared spectrum of bamboo cell wall in situ condition. The characteristic peak positions of Nano-IR spectrum is basically the same with that of microscopic FTIR spectrum, indicating that Nano-IR spectrum can reveal the chemical information of bamboo cell wall. The results of the present work suggested that nano-IR technology could be an effective research tool in research of nano chemical composition distribution of bamboo cell wall.

[Study on the Crystal Structure of Cellulose in Bamboo with Synchrotron Radiation Wide Angle X-Ray Scattering].

The crystal structure of cellulose will directly affect the properties of bamboo fiber -reinforced composite, but the unit cell of native cellulose in bamboo has never been investigated. The most accepted model for the structure of native cellulose is Meyer-Misch model which provides a reference to understand the unit cell of native cellulose in bamboo. The native cellulose consists of two different crystal structures (Ⅰ(α) and Ⅰ(ß)) which exist in different plants with different proportions. Because of this situation, the crystal structure of bamboo cellulose should have a unique model. The moso bamboo (Phyllostachys edulis (Carr. ) H. de Lehaie)was selected. The crystal structure of cellulose of bamboo was investigated with two dimensional synchrotron radiation wide angle X-ray scattering (SR-WAXS). The values of the interplanar spacings of each peak were obtained from SR-WAXS patterns, and then crystal structure parameters were calculated according to monoclinic crystal system. The results show that the fibre axis of a bamboo cellulose unit cell with a monoclinic unit cell of a=8.35 Å, b (fiber axis)=10.38 Å, c=8.02 Å, ß=84.99°. This model has a two antiparallel arrangement for the chains in unit cell, with four glucose residues. Thus, the model may be used to provide a theoretical basis for high value-added bamboo fiber -reinforced composite.

[Modified Mechanism of Cell Walls from Chinese Fir Treated with Low-Molecular-Weight Phenol Formaldehyde Resin].

Study on the modified mechanism of wood cell walls, it is very important for improving treatment reagents, optimizing treatment technology, and enhancing wood density, mechanical properties, dimensional stability, and so on. Samples of plantation Chinese fir were treated gradually with synthesized water-soluble low-molecular-weight phenol formaldehyde (PF) resins under vacuum and pressure. The correlated physical and chemical properties of the treated and untreated reference samples were determined by X-ray diffractometer (XRD), Fourier transform infrared spectrometer (FTIR), and nuclear magnetic resonance spectrometer(NMR) (Using method of Cross Polarization/Magic Angle Spinning for continuous testing) with high precision and resolution. The results showed that, after treated with water-soluble low-molecular-weight PF resin, the average values of crystallinity from the treated samples were decreased obviously, and the average reduction rate was 12.67%, 11.91% and 6.26%, respectively. Comparing water-soluble, low-molecular-weight PF resin modified Chinese fir with untreated reference samples, no new chemical shifts and characteristic peaks of functional groups from esters, ethers, etc. were present by using FTIR and ¹³C NMR spectrum. It was considered that there was no distinct chemical reaction between the water-soluble low-molecular-weight PF resin and Chinese Fir cell walls. But water-soluble low-molecular-weight PF resin could enter into the structure relatively loose, large size spaces, relatively area large amorphous regions in cell walls of Chinese fir tracheids, and form physical filling, which resulting in the decreasing of relative crystallinity. This study has important reference value for the development of new wood modification reagents and the optimization of wood modification process. The findings also provide important theoretical foundation for further proving the modification mechanisms of wood cell walls and enriching the modified theories of wood cell walls.

Properties enhancement of poly(ß-hydroxybutyrate) biocomposites by incorporating surface-modified wheat straw flour: Effect of pretreatment methods.

Poly(3-hydroxybutyrate) (PHB) biocomposites filled with wheat straw flour (WSF) were enhanced through modifying WSF surface by pretreatments, i.e., alkali solution (NaOH 1-7 wt%) dipping, (3-aminopropyl)triethoxysilane solution (APTES 0.5-2 wt%) soaking, or NaOH+APTES synergistic impregnation. The WSF was characterized by microscopy, spectroscopy, diffractometry, thermogravimetry, and wetting. Through different levels of surface etching effect or grafting functional groups, all the pretreatments removed unstable, amorphous substances on WSF, obtaining higher crystallinity by 2-12 %, degradation temperature by 57-83 °C, and lower water contact angle by 7-24°. Compression-molded WSF/PHB biocomposites were examined by mechanical tests, microscopy (fracture morphology), water absorption, calorimetry, and thermogravimetry. Above pretreatments boosted mechanical-, moisture-, and heat-resistances of composites, owing to stronger interfacial interaction of PHB with surface-modified WSF, and the improved physicochemical properties of WSF itself. Alkali treatment worked better in raising mechanical, waterproof behaviors, while silane induced higher temperature for phase transition, decomposition. Enhancement achieved by alkali+silane could surpassed both single treatments. The best outcome occurred in 3 wt% NaOH + 0.5 wt% APTES, which increased strength (flexural, tensile, and impact), modulus (flexural, tensile) by 22-40 % and 14-23 %, respectively, decreased 300 h-water absorption by 18 %, and rose melting, degradation temperatures by 2 and 23 °C, respectively, showing new potential for construction-related application.

Structural Characteristics of Reaction Tissue in Plants.

To maintain or adjust posture under the challenges of gravity and increased self-weight, or the effects of light, snow, and slope, plants have the ability to develop a special type of tissue called reaction tissue. The formation of reaction tissue is a result of plant evolution and adaptation. The identification and study of plant reaction tissue are of great significance for understanding the systematics and evolution of plants, the processing and utilization of plant-based materials, and the exploration of new biomimetic materials and biological templates. Trees' reaction tissues have been studied for many years, and recently, many new findings regarding these tissues have been reported. However, reaction tissue requires further detailed exploration, particularly due to their complex and diverse nature. Moreover, the reaction tissues in gymnosperms, vines, herbs, etc., which display unique biomechanical behavior, have also garnered the attention of research. After summarizing the existing literature, this paper provides an outline of the reaction tissues in woody plants and non-woody plants, and lays emphasis on alternations in the cell wall structure of the xylem in softwood and hardwood. The purpose of this paper is to provide a reference for the further exploration and study of reaction tissues with great diversity.

[Distribution of lignin in Chinese fir branches determined by ultraviolet microspectrometer].

Distribution of lignin in the cell walls of Chinese fir branches emerged in the spring season were first studied by using ultraviolet microscope based on their cell microstructure observation and lignin qualitative measurement by the lightmicroscope and confocal laser scanning microscope. The results showed that the contents of lignin are inhomogeneously distributed in different micro-areas of the cell walls. The order of lignin concentrations is the cell corner>the middle lamellar>the secondary with the absorbance values of ultraviolet wave of 0.489, 0.307 and 0.278, respectively. The result of quantitative analysis consists with that of qualitative analysis. A new measurement method was proposed to study the distribution of lignin content in wood cell walls in CFhina.

Tung Oil Thermal Treatment Improves the Visual Effects of Moso Bamboo Materials.

Color is one of the most important characteristics of a material's appearance, which affects the additional value of bamboo and psychological feelings of users. Previous studies have shown that the dimensional stability, mildew resistance and durability of bamboo were improved after tung oil thermal treatment. In this study, the effects of tung oil thermal treatment on bamboo color at different temperatures and durations of time were investigated. The results show that the lightness (L*) of bamboo decreased as the tung oil temperature or duration of time increased. The red-green coordinates (a*) and color saturation (C*) of bamboo were gradually increased as the tung oil temperature rose from 23 °C to 160 °C, while the a* and C* were gradually decreased when the temperature continued to rise from 160 °C to 200 °C. There was no significant difference in the yellow-blue coordinates (b*) of bamboo when the duration was prolonged from 0.5 h to 3 h with tung oil thermal treatment at 140 °C. Eye movement data show that the popularity of bamboo furniture was significantly improved at 23-100 °C and slightly improved at 160-180 °C with tung oil treatment. Therefore, tung oil thermal treatment plays a positive role in improving visual effects and additional value of bamboo.

Effects of Accelerated Ageing by Humidity and Heat Cycles on the Quality of Bamboo.

The effect of humidity and heat environmental conditions on the durability of conventional bamboo materials is a pressing issue in the reserving phase of biomass materials. In this study, the relationship between the main physicochemical, pyrolytic, and mechanical properties of bamboo before and after ageing has been investigated. Exposure of engineered bamboo raw materials with moisture content up to 10% to alternating humidity and heat cycles (20 °C 98% RH-30 °C 64% RH-40 °C 30% RH) of ageing (HHT) causes degradation of the chemical polymer matrix. Byk Gardner 6840 color difference meter, X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), compression intensity, thermogravimetric-infrared spectroscopy (TG-IR), and density changes are used to assess the quality of the material before and after ageing. No significant changes in the moisture content within the range of 6.12 ± 0.327 after two weeks of the engineered bamboo during wet thermal cyclic ageing were determined. However, there were significant differences in mass loss (7.75-9.93 g), cellulose crystallinity, chemical changes, compression strength, and pyrolytic properties. Differences in specimen colors were observed during 10 weeks of the accelerated humidity heat cycling ageing, and TCD variations ranged from 3.75 to 20.08 and from 0.25 and 3.24, respectively. Reduced cellulose crystallinity (36.459-22.638%), axial compressive strength (63.07-88.09 MPa), and modulus of rupture (2409-4286 MPa) were found during aging, whereas deformation and ductility properties were improved. Both natural and humidity heat ageing improve thermal stability and peak pyrolysis rates (0.739-0.931; 0.731-0.797). Humidity heat cyclic ageing will assist in the design and risk assessment of warehousing environments for industrial applications.

Effect of bending on radial distribution density, MFA and MOE of bent bamboo.

One of the excellent characteristics of bamboo is the deformation stability. However, the reasons for the good bending stability of bamboo have not been well studied. In this study, we examined the pathways that controls bending deformation in bamboo. A hand-bent phyllostachys iridescens member was chosen to examine continuous density distribution, microfibril angle (MFA) and modulus of elasticity (MOE) along radial direction using SilviScan analysis. Our results show that in bent bamboo, MFA is lower in tension sample and higher in compression sample than neutral sample. There is a strong linear positive correlation between density and MOE, while negative linear correlation between MOE and MFA and no obvious linear correlation between MFA and density. Increased bending was influential in primarily changing the MOE, while also altering the density distribution and MFA. Our results demonstrate variation in density, MOE and MFA distribution along radial direction of tension, neutral and compression samples, which play an important role in maintaining the bending characteristics of bamboo.

In-situ visualizing selective lignin dissolution of tracheids wall in reaction wood.

As a renewable biological macromolecule with aromatic structure, lignin can serve as matrix substance to maintain cell wall integrity and is regarded as the natural biomass recalcitrance. Substantial differences in the cell wall lignin topochemistry between opposite (Ow) and compression wood (Cw) trachieds in Pinus bungeana Zucc. were visualized during [Emim][OAc] pretreatment at room temperature. The ionic liqiuds treatment induced a more obvious wall swelling for highly lignified Cw tracheids than that of Ow, while dynamic Raman spectra analysis indicated the higher lignin and carbohydrates removal for Ow tracheids. Raman imaging further revealed that both lignin and carbohydrates were dissolved simultaneously within the middle lamella and secondary wall of Ow and pretreatment has little effects on Cw tracheids wall. Moreover, it was demonstrated that lignin composition was the key factor to affect the composition dissolution. In particular, lignin G-units were selectively removed from cell corner middle lamella (52.3 %) and secondary wall (62.0 %) of Ow tracheids. When cotton fiber, as a reference was treated under the same conditions, lattice conversion moving from cellulose I to II occurred. The findings confirmed the important role of lignin compostion in the dissolution behavior of carbohydrate dominant tracheids wall.

Using Statistical Methods to Comparatively Analyze the Visual Characteristics of Flattened Bamboo Boards in Different Bamboo Culms.

Different flattened bamboo boards will produce different visual effects, which directly determine consumers' preferences. However, their visual characteristics were unknown. To clarify the visual effects of flattened bamboo boards in different bamboo culms, the visual, physical, and psychological quantities were firstly studied using their quantitative color and glossiness measurements, combined with quantitative semantic differential and statistical methods. Key results revealed that the values of lightness L* and blue-yellow index b* from the base to the top of the bamboo culms tended to decrease gradually, while green-red index a* values exhibited an increasing trend, and glossiness GZL (GZT) showed no significant difference. The L* value of bamboo outer layer (30.18) was smaller than that of the outer (61.90) and the inner (68.68), which had an increasing trend from the outside to the inside of the bamboo culm, while the GZL (GZT) values corresponded to 6.07 (4.66), 4.51 (3.12), and 2.77 (2.55), showing an opposite trend. The a* and b* values present a rise-fall tendency. According to visual psychological assessment, the outer was reflected as an "artificial-decorative", "smooth-warm", and "comfort-sophisticated" feeling; the inner had an "artificial-practical", "smooth-warm", and "comfort-sophisticated" sense; the bamboo outer layer had an "nature-practical", "rough-cold", and "sick-primitive" sense. Furthermore, predictive models for visual psychological quantities were constructed. This work provides a theoretical data basis for furniture design and standard materials application of flattened bamboo boards.

The Global Atlas of Bamboo and Rattan (GABR) Phase II: new resources for sustainable development.

Bamboo, the fast-growing grass plant, and rattan, the spiky climbing palm, are both essential forest resources that have been closely linked with human lives, livelihoods and material culture since ancient times. To promote genetic and genomic research in bamboo and rattan, a comprehensive and coordinated international project, the Genome Atlas of Bamboo and Rattan (GABR), was launched in 2017. GABR achieved great success during Phase I (2017-2022). We will focus on investigating and protecting bamboo and rattan germplasm resources in Phase II ( 2022-2027). Here, we briefly review the achievements of Phase I and introduce the goals of Phase II.

[Study on bamboo treated with gamma rays by X-ray diffraction].

The microfibril angle and crystallinity of bamboo treated with gamma rays were tested by X-ray diffraction (XRD). The result indicated that crystallinity in bamboo increased when irradiation dose was less than 100 kGy, while the irradiation dose was raised to about 100 kGy, crystallinity in bamboo reduced. But during the whole irradiation process, the influence on microfibril angle was not obvious, so it was not the dominant factors on variation in physical-mechanical properties of bamboo during the process of irradiation.

[Study on chemical compositions and crystallinity changes of bamboo treated with gamma rays].

The structures and qualities of main chemical compositions in cell wall of bamboo treated with gamma rays were tested by nuclear magnetic resonance spectrometer (NMR) and X-ray Diffraction (XRD). The result indicated that the bamboo crystallinity increased at the beginning of irradiation process, while the crystallinity reduced when the irradiation dose was raised to about 100 kGy. During the whole irradiation process, hemicellulose degraded, and with the irradiation doses increased the non-phenolic lignin changed to the phenolic.

Incorporation of In Situ Synthesized Nano-Copper Modified Phenol-Formaldehyde Resin to Improve the Mechanical Properties of Chinese Fir: A Preliminary Study.

Phenol-formaldehyde (PF) resin, modified using nano-copper with varying contents (0 wt%, 1 wt%, 3 wt%), was manufactured to improve the mechanical properties of Chinese fir. The morphology, chemical, micromechanical and micromechanical properties of the samples were determined by transmission electron microscopy (TEM), atomic force microscopy (AFM), environmental scanning electron microscopy (ESEM), Fourier transform infrared spectroscopy (FTIR), nanoindentation (NI) and traditional mechanical testing. The TEM and AFM results indicated that the in situ synthesized nano-copper particles were well-dispersed, and spherical, with a diameter of about 70 nm in PF resin. From the FTIR chemical changes detected by FTIR inferred that the nano-copper modified PF resin penetrated into the Chinese fir cell walls and interacted with the acetyl groups of hemicellulose by forming a crosslinked structure. Accordingly, the micro-mechanical properties of the Chinese fir cell walls were enhanced after treatment with nano-copper modified PF resin. The filling of the PF-1-Cu resin (1 wt% nano-copper) in the wood resulted in 13.7% and 22.2% increases in the elastic modulus (MOE) and hardness, respectively, of the cell walls. Besides, the impact toughness and compressive strength of the Chinese fir impregnated with PF-1-Cu resin were 21.8% and 8.2% higher than that of the PF-0-Cu resin. Therefore, in situ synthesized nano-copper-modified PF resin is a powerful treatment method for Chinese fir due to improved diffusive properties and reinforcement of the mechanical properties.

Effect of Rosin Modification on the Visual Characteristics of Round Bamboo Culm.

Rosin was used to treat round bamboo culm using the impregnation method. The quantitative color and gloss measurements combined with a qualitative eye tracking experiment were used to evaluate the effect of rosin treatment under different temperatures on the visual characteristics of the bamboo surface. Surface morphology analysis was also used to explore the mechanism of modification. The results showed that proper heating of the modified system was conducive to the formation of a continuous rosin film, which increased the gloss value. The maximum gloss value of 19.6 achieved at 50 °C was 122.7% higher than the gloss value of the control group. Heating decreased the brightness of the bamboo culm and changed the color from the green and yellow tones to red and blue. Additionally, at temperatures higher than 60 °C, the bamboo epidermal layer was damaged or shed, and stripes formed on the culm surface. The density of these stripes increased with an increase in treatment temperature. Eye movement experiment and subjective evaluation showed that high gloss would produce dazzling feeling, such as at 50 °C, while low gloss will appear dim, such as at 80 °C, while the gloss at 40 °C and 60 °C were appropriate. Additionally, the solid color surface below 60 °C had a large audience of about 73%, and the striped surface above 60 °C was preferred by 27% of the subjects.