Exploring an eco-friendly approach to improve soil tensile behavior and cracking resistance

Soil tensile strength is a critical parameter governing the initiation and propagation of tensile cracking.This study proposes an eco-friendly approach to improve the tensile behavior and crack resistance of clayey soils.To validate the feasibility and efficacy of the proposed approach,direct tensile tests were employed to determine the tensile strength of the compacted soil with different W-OH treatment concentrations and water contents.Desiccation tests were also performed to evaluate the effectiveness of W-OH treatment in enhancing soil tensile cracking resistance.During this period,the effects of W-OH treatment concentration and water content on tensile properties,soil suction and microstructure were investigated.The tensile tests reveal that W-OH treatment has a significant impact on the tensile strength and failure mode of the soil,which not only effectively enhances the tensile strength and failure displacement,but also changes the brittle failure behavior into a more ductile quasi-brittle failure behavior.The suction measurements and mercury intrusion porosimetry(MIP)tests show that W-OH treatment can slightly reduce soil suction by affecting skeleton structure and increasing macropores.Combined with the microstructural analysis,it becomes evident that the significant improvement in soil tensile behavior through W-OH treatment is mainly attributed to the W-OH gel's ability to provide additional binding force for bridging and encapsulating the soil particles.Moreover,desiccation tests demonstrate that W-OH treatment can significantly reduce or even inhibit the formation of soil tensile cracking.With the increase of W-OH treatment concentration,the surface crack ratio and total crack length are significantly reduced.This study enhances a fundamental understanding of eco-polymer impacts on soil mechanical properties and provides valuable insight into their potential application for improving soil crack resistance.

Sustainable, thermoplastic and hydrophobic coating from natural cellulose and cinnamon to fabricate eco-friendly catering packaging

Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which significantly affect the overall degradation performance of products.It is imperative and attractive to develop biodegradable functional coatings.Herein,we proposed a novel strategy to successfully prepare biodegradable,thermoplastic and hydrophobic coatings with high transparence and biosafety by weakening the interchain interactions between cellulose chain.The natural cellulose and cinnamic acid were as raw materials.Via reducing the degree of polymerization(DP)of cellulose and regulating the degree of substitution(DS)of cinnamate moiety,the obtained cellulose cinnamate(CC)exhibited not only the thermalflow behavior but also good biodegradability,which solves the conflict between the thermoplasticity and biodegradability in cellulose-based materials.The glass transition temperature(T_(g))and thermalflow temperature(T_(f))of the CC could be adjusted in a range of 150–200℃ and 180–210℃,respectively.The CC with DS<1.2 and DP≤100 degraded more than 60%after an enzyme treatment for 7 days,and degraded more than 80%after a composting treatment for 42 days.Furthermore,CC had no toxicity to human epidermal cells even at a high concentration(0.5 mg mL^(-1)).In addition,CC could be easily fabricated into multifunctional coating with high hydrophobicity,thermal adhesion and high transparence.Therefore,after combining with cellophane and paperboard,CC coating with low DP and DS could be used to prepare fully-biodegradable heat-sealing packaging,art paper,paper cups,paper straws and food packaging boxes.

Harnessing eco-friendly additives to manipulate zinc-ion solvation structures towards stable zinc metal batteries

Considerable research efforts have been dedicated to investigating the side reactions and the growth of Zn dendritic in aqueous zinc-ion batteries(AZIBs).The incorporation of organic solvents as additives in electrolytes has yielded highly promising results.Nevertheless,their pervasive use has been hindered by concerns regarding their toxicity,flammability,and economic viability.Herein,we propose the utilization of γ-valerolactone(γ-V),a novel eco-friendly solvent,as an alternative for conventional organic additives to improve the performance of Zn anode.Experimental investigations and theoretical analyses have verified that γ-V additives can diminish the Zn^(2+)-desolvation energy and enhance Zn^(2+) transport kinetics.The adsorbed γ-V molecules modulate the nucleation and diffusion of Zn^(2+),facilitating Zn growth along the(002) crystal plane,thus inhibiting dendrite formation and side reactions.Consequently,the modified electrolyte with 3% γ-V exhibit highly reversible cycling for 2800 h at1 mA cm^(-2) and 1 mA h cm^(-2) in Zn//Zn symmetric cell.The Zn//KVOH coin cells deliver a capacity retention of 74.7% after 1000 cycles at 5 A g^(-1).The Zn//KVOH pouch cells maintain a capacity retention of78.7% over 90 cycles at 3 A g^(-1).Notably,the γ-V additives also effectively alleviate the self-discharge phenomenon.This work provides valuable insights on the development of aqueous zinc-ion batteries with superior safety through the modulation of electrolytes using eco-friendly additives.

Thermo-Mechanical, Physico-Chemical, Morphological, and Fire Characteristics of Eco-Friendly Particleboard Manufactured with Phosphorylated Lignin Addition

Lignin,lignosulfonate,and synthesized phosphorylated lignosulfonate were introduced as greenfillers in citric acid-sucrose adhesives for bonding particleboard fabricated from areca leaf sheath(ALS).The characteristics of particleboards were compared to that of ultralow emitting formaldehyde(ULEF-UF).Thefillers derived from Eucalyptus spp.kraft-lignin were added forflame retardancy enhancement.10%of each lignin and modified lig-nin was added into the ULEF-UF and citric acid-sucrose bonded particleboards.Analyses applied to particle-boards included thermal characteristics,X-ray diffraction analysis(XRD),morphological properties,Fourier transform infrared spectroscopy(FTIR),as well as physical,mechanical,andfire resistance characteristics of the laboratory-fabricated particleboards.Lignin and modified lignin resulted in improved thermal stability of the composites bonded with ULEF-UF while the improvement in the particleboard bonded with citric acid-sucrose was not significant.The introduction offiller exerted a higher influence on the UF-bonded particleboards compared to composites fabricated with citric acid-sucrose.Generally,the presence of lignin,lignosulfonate,and phosphorylated lignosulfonate enhanced the mechanical strength of the ULEF-bonded particleboards,although their dimensional stability has deteriorated.Markedly,the use of lignin and lignosulfonate enhanced thefire resis-tance of the particleboards produced with lower observed weight loss.All laboratory particleboards exhibited satisfactoryfire resistance,attaining a V-0 rating in according to the UL-94 standard.

Atomic-scale engineering of advanced catalytic and energy materials via atomic layer deposition for eco-friendly vehicles

Zero-emission eco-friendly vehicles with partly or fully electric powertrains have exhibited rapidly increased demand for reducing the emissions of air pollutants and improving the energy efficiency. Advanced catalytic and energy materials are essential as the significant portions in the key technologies of eco-friendly vehicles, such as the exhaust emission control system,power lithium ion battery and hydrogen fuel cell. Precise synthesis and surface modification of the functional materials and electrodes are required to satisfy the efficient surface and interface catalysis, as well as rapid electron/ion transport. Atomic layer deposition(ALD), an atomic and close-to-atomic scale manufacturing method, shows unique characteristics of precise thickness control, uniformity and conformality for film deposition, which has emerged as an important technique to design and engineer advanced catalytic and energy materials. This review has summarized recent process of ALD on the controllable preparation and modification of metal and oxide catalysts, as well as lithium ion battery and fuel cell electrodes. The enhanced catalytic and electrochemical performances are discussed with the unique nanostructures prepared by ALD. Recent works on ALD reactors for mass production are highlighted. The challenges involved in the research and development of ALD on the future practical applications are presented, including precursor and deposition process investigation, practical device performance evaluation, large-scale and efficient production, etc.

Eco-friendly physical blowing agent mass loss of bio-based polyurethane rigid foam materials

Through systematical experiment design, the physical blowing agent(PBA) mass loss of bio-based polyurethane rigid foam(PURF)in the foaming process was measured and calculated in this study, and different eco-friendly PBA mass losses were measured quantitatively for the first time. The core of the proposed method is to add water to replace the difference, and this method has a high fault tolerance rate for different foaming forms of foams. The method was proved to be stable and reliable through the standard deviations σ1and σ2for R1(ratio of the PBA mass loss to the material total mass except the PBA) and R2(ratio of the PBA mass loss to the PBA mass in the material total mass) in parallel experiments. It can be used to measure and calculate the actual PBA mass loss in the foaming process of both bio-based and petroleumbased PURF. The results show that the PBA mass loss in PURF with different PBA systems is controlled by its initial mass content of PBA in PU materials ω. The main way for PBA to dissipate into the air is evaporation/escape along the upper surface of foam. This study further reveals the mechanism of PBA mass loss: the evaporation/escape of PBA along the upper surface of foam is a typical diffusion behavior. Its spread power comes from the difference between the chemical potential of PBA in the interface layer and that in the outside air. For a certain PURF system, R1has approximately linear relationship with the initial mass content of PBA in PU materials ω, which can be expressed by the functional relationship R1= kω, where k is a variable related to PBA’s own attributes.

One-step Eco-friendly Fabrication of Antibacterial Polyester Via On-line Amination Reaction by Melt Coextrusion

The work is dedicated to develop a one-step eco-friendly method to prepare antibacterial polyethylene terephthalate(PET).We report a one-step eco-friendly method to manufacture antibacterial PET via on-line amination reaction by melt coextrusion.Beside evenly mixing of poly(hexamethylene guanidine)(PHMG)and PET in the melt coextrusion procedure,the amination reaction also occurred between PHMG and PET under high temperature(230-270℃).The antibacterial ability of composite PET showed obvious PHMG concentration dependence,and antibacterial activity reached more than 99%when PHMG content was 2.5 wt%.Moreover,LIVE/DEAD fluorescence test further confirmed that the composite PET could kill bacteria quickly and efiectively(within 30 min);while negligible cytotoxicity was observed to HSF and HUVEC cells.Onestep eco-friendly fabrication of composite antibacterial PET was accomplished by on-line melt coextrusion.The composite antibacterial PET has potential use in multiple fields to combat with pathogenic including textiles,packaging materials,decoration materials and biomedical devices,etc.

Eco-Friendly Knit Garments Washing Implementation and Its Impact

Environment pollution is one of the major threats to today’s world and researchers say most of the pollution comes from the washing industry.So,the study aims to find out an alternative way to the existing chemical wash process of the washing industry to save the environment.To conduct this study,one knit washing factory has been selected that has eco-friendly wash facilities.The eco-friendly wash process samples have been developed and finally show the comparison in respect of time,per day production and test result to the conventional chemical wash processes along with the impact of production cost on the garment.For all eco-friendly process,it has been found that water consumptions are too less in comparison with conventional process potentials which is partially related to Sustainable Development Goals 13(Climate Action).This study might help to find out a new era of doing washed knitted product business without polluting the environment.

基于筛分配比的超薄纤维板物理力学性能研究

为优化超薄纤维板的生产工艺,提高超薄纤维板生产效率与生产质量,通过筛分重组,探究纤维尺寸、配比对超薄纤维板的影响。结果表明:在相同的热压条件下,粗纤维的含量越高,超薄纤维板的吸水厚度膨胀率越高。单一尺寸纤维制备的超薄纤维板静曲强度、弹性模量随着纤维尺寸的增大而提高。不同尺寸混合纤维制备的超薄纤维板,当粗纤维、中长纤维和细纤维的比例为6:3:1时,静曲强度和弹性模量达到最大。

中国纤维板产业发展现状及问题探讨

介绍了我国纤维板产业发展现状、产品类型、产量、市场动态和国际贸易等情况,分析了近年我国纤维板消费量大幅下降的原因,并提出了创新产品和技术、拓展应用范围的良性发展解决方案,以期拓宽纤维板产品的应用领域,促进产业的可持续增长和创新。

2022年欧美以外其他地区中密度纤维板产能概况

对亚洲、南美洲、大洋洲和非洲地区主要国家中密度纤维板年产能、新增产能情况进行介绍。2022年,亚洲、南美洲、大洋洲和非洲等欧美以外地区,中密度纤维板年产能为8810.7万m^(3),2023年及其后总年产能将达到9474.9万m^(3)。

Grindability Evaluation of Ultrasonic Assisted Grinding of Silicon Nitride Ceramic Using Minimum Quantity Lubrication Based SiO_(2)Nanofluid

Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining systems.It involve the spray of an infinitesimal amount of mist-like lubricants during machining processes.The MQL system is affirmed to exhibit an excellent machining performance,and it is highly economical.The nanofluids are understood to exhibit excellent lubricity and heat evacuation capability,compared to pure oil-based MQL system.Studies have shown that the surface quality and amount of energy expended in the grinding operations can be reduced considerably due to the positive effect of these nanofluids.This work presents an experimental study on the tribological performance of SiO_(2)nanofluid during grinding of Si_(3)N_(4)ceramic.The effect different grinding modes and lubrication systems during the grinding operation was also analyzed.Different concentrations of the SiO_(2)nanofluid was manufactured using canola,corn and sunflower oils.The quantitative evaluation of the grinding process was done based on the amount of grinding forces,specific grinding energy,frictional coefficient,and surface integrity.It was found that the canola oil exhibits optimal lubrication performance compared to corn oil,sunflower oil,and traditional lubrication systems.Additionally,the introduction of ultrasonic vibrations with the SiO_(2)nanofluid in MQL system was found to reduce the specific grinding energy,normal grinding forces,tangential grinding forces,and surface roughness by 65%,57%,65%,and 18%respectively.Finally,regression analysis was used to obtain an optimum parameter combinations.The observations from this work will aid the smooth transition towards ecofriendly and sustainable machining of engineering ceramics.

免拆纤维板底模钢筋桁架叠合板受弯性能试验

免拆纤维板底模钢筋桁架叠合板适用于民用建筑和工业建筑,具有较好的经济性与施工便利性.为研究底模与混凝土的协同受力情况,对12块足尺纤维板底模钢筋桁架叠合板进行静力试验,分别研究桁架间距和跨度对免拆底模叠合板力学性能的影响及免拆底模对叠合板的抗裂性能和破坏模式的影响,测得了相应的荷载-挠度曲线、荷载-应变曲线、裂缝开展及分布状况、破坏形式及相应的破坏荷载等.结果表明:免拆纤维板底模钢筋桁架叠合板破坏模式均为受弯破坏,但由于纤维板的材料特性,其破坏模式与混凝土底板存在差异,水泥基纤维板开裂无明显前兆,开裂突然,表现为纤维板整体性拉断,且多为半贯通、贯通裂缝;纤维板底模与后浇混凝土的协同受力性能良好,叠合面未出现滑移现象,所采用的自攻螺丝连接方式可满足叠合面的抗剪需求;减小桁架间距会提升叠合板的极限承载力,桁架间距对屈服荷载影响较小;下弦与上弦钢筋应变均得到了充分的发展,桁架腹杆应变较为复杂,在整个受力过程均保持弹性状态,各部位应变随着纤维底板的开裂也产生一定波动;采用截面换算法,提出纤维板底模钢筋桁架叠合板底板开裂应力近似计算公式,计算结果表明纤维底板的开裂应力较混凝土底板有较大程度提升,即采用纤维底板可提升叠合板的抗裂性能.

应用响应面法优化超薄高密度纤维板饰面胶合板的热压工艺参数

为提高超薄高密度纤维板饰面胶合板的性能,利用响应面法(Box-Behnken)优化其热压工艺参数。以杨木单板(替代胶合板)、超薄高密度纤维板为试验材料,以热压温度(120、130、140、150、160℃)、热压时间(50、100、150、200、250 s)、热压压力(0.4、0.6、0.8、1.0、1.2 MPa)为影响因素,以超薄高密度纤维板饰面表面胶合强度、浸渍剥离长度为评价指标,采用单因素试验分析热压工艺(热压温度、热压时间、热压压力)对超薄高密度纤维板饰面的表面胶合强度和浸渍剥离长度的影响;采用响应面法设计多因素正交旋转组合试验,对试验设计范围内的影响因素进行优化热压参数组合、确定最优工艺参数。结果表明:热压温度对表面胶合强度的影响极显著,热压温度和热压压力对浸渍剥离长度影响极显著,热压时间和热压压力对浸渍剥离长度有显著的协同作用,共同影响板材的性能;试验范围内的最优工艺参数:热压温度150℃、热压时间210 s、热压压力0.8 MPa,板材的表面胶合强度为1.49 MPa、浸渍剥离长度为15 mm。

气鼓轮砂带砂光饰面中密度纤维板的磨削力与表面粗糙度

【目的】探究气鼓轮砂带砂光参数对磨削力的影响以及磨削力与砂光表面粗糙度的关系,为更好控制气鼓轮砂带砂光木(板)材的表面粗糙度提供理论参考。【方法】开展气鼓轮砂带砂光饰面中密度纤维板的单因素试验,运用流体腔理论建立气鼓轮砂带砂光饰面中密度纤维板的有限元模型,基于有限元模型和单因素试验,探究气鼓轮气压、进给量、轴平行度误差对磨削力和砂光表面粗糙度的影响,并分析磨削力与砂光表面粗糙度的关系。【结果】随着气鼓轮气压、进给量、轴平行度误差增加,试件总磨削力增大,但其引起总磨削力增大的原因不同;试件接触中心节点法向应力大小主要与气鼓轮气压有关;对应同一试件的中间区域(6~59 mm),气鼓轮气压组和进给量组试件的局部磨削力近似相等,轴平行度误差组试件的局部磨削力与位置近似线性相关;气鼓轮气压对试件磨削力和表面粗糙度影响较小,进给量可较明显改善试件表面粗糙度;试件表面粗糙度与局部磨削力的线性拟合相关系数R2为0.975,与总磨削力的线性拟合相关系数R2为0.871,表面粗糙度与局部磨削力的线性相关性更好。【结论】气鼓轮砂带砂光饰面中密度纤维板的有限元模型可以准确计算试件磨削力;分析气鼓轮磨削力与试件砂光表面粗糙度的关系时,选择试件局部磨削力比试件总磨削力和试件法向应力更好。

碳酸钙对三聚氰胺脲醛树脂胶黏剂性能的影响

三聚氰胺脲醛(MUF)树脂在我国的应用十分广泛。为了通过使用少量的改性剂对MUF树脂胶合强度和耐水性等方面起到较积极作用,利用200目(0.074mm)碳酸钙粉体作为MUF树脂的改性剂,采用普通脲醛树脂合成工艺制备改性MUF树脂,改性剂用量仅为树脂总质量的0.5%。测试各组树脂的理化性能,同时测试了使用树脂制备中密度纤维板的物理力学性能。结果表明:碳酸钙的加入显著提升了MUF树脂的黏度和固化时间;碳酸钙作为改性剂能显著提升MUF树脂制备纤维板的各项力学性能,其MOR提升超过15%,至39.23 MPa;改性MUF树脂制备板材的耐水性能也有所提升。

Optimization Mechanism of Mechanical Properties of Basalt Fiber-Epoxy Resin Composites by Interfacially Enriched Distribution of Nano-Starch Crystals

Fibre reinforced polymer composites have become a new generation of structural materials due to their unique advantages such as high specific strength,designability,good dimensional stability and ease of large-area monolithic forming.However,the problem of interfacial bonding between the resin matrix and the fibres limits the direct use of reinforcing fibres and has become a central difficulty in the development of basalt fibre-epoxy composites.This paper proposes a solution for enhancing the strength of the fibre-resin interface using maize starch nanocrystals,which are highly yield and eco-friendly.Firstly,in this paper,corn starch nanocrystals(SNC)were prepared by hydrolysis,and were deposited on the surface of basalt fibers by electrostatic adsorption.After that,in order to maximize the modification effect of nano-starch crystals on the interface,the basalt fiber-epoxy resin composite samples were prepared by mixing in a pressureless molding method.The test results shown that the addition of basalt fibers alone led to a reduction in the strength of the sample.Deposition of 0.1 wt%SNC on the surface of basalt fibers can make the strength consistent with pure epoxy resin.When the adsorption amount of SNC reached 0.5 wt%,the tensile strength of the samples was 23.7%higher than that of pure epoxy resin.This is due to the formation of ether bond homopolymers between the SNC at the fibre-epoxy interface and the epoxy resin,which distorts the originally smooth interface,leading to increased stress concentration and the development of cracks.This enhances the binding of basalt fibers.The conclusions of this paper can provide an effective,simple,low-cost and non-polluting method of interfacial enhancement modification.

室内型乒乓球台面用纤维板生产工艺研究

在不改变纤维板现行制胶和热压设备的条件下,研制新胶种和新工艺,生产一种室内型乒乓球台台面用纤维板新产品。新产品关键指标:密度≥680 kg/m^(3),表层密度≥1040 kg/m^(3),内结合强度≥0.60 MPa,静曲强度≥29 MPa,游离甲醛≤6 mg/100 g,吸水厚度膨胀率≤10%,油漆后板面光滑度、平整度、弹性要求、尺寸等各项性能指标符合室内型乒乓球台台面要求,适用于娱乐、训练、专业比赛等。

Integration of Environmental and Social Values in Cultural Spaces:Sustainable and Inclusive Wayfinding Materials for Museums

In the context of use of large museum centers,numerous national and international methodological experiments show that the wayfinding project must consider the needs of both habitual users(user-centered design)and local communities(design for communities)and the importance of environmental protection(eco-design)as a priority interest of the community.This“double target”,“user-centered”and“environment-centered”can be applied during the selection process of materials to be used in the project.With respect to these possibilities,this contribution intends to present the results of research focused on material characterization of the reception and distribution spaces of large museum centers.This characterization is based on use of sensory materials and aims to evaluate their impact on the usability and sustainability of wayfinding systems.The paper directed towards a proposal for organization of integrated information on new generation so-called smart materials;within the design of a wayfinding system,these can balance the aesthetic-perceptual and performance and environmental impact,in order to allow designers to make informed decisions oriented towards inclusion and sustainability.The study was addressed by conducting two phases of systematic literature and library review of materials.The investigations conducted led to achievement of a first research result which consists in the identification of a“standard sheet”for the mapping and cataloging of the materials used for wayfinding.The“standard sheet”allows organizing the information on smart,sensorial,and eco-friendly materials,balancing the aesthetic-perceptive component with the performance on the environmental impact along the entire life cycle in a circular perspective.This tool could guide designers towards an environmental communication project oriented towards sustainability and is effective for usability and wayfinding.

Synthesis and Characterization of Local Bio-Sourced Geopolymer Binder:Application to Compressed Earth

The construction industry continues to rely on conventional materials like cement,which often can come with a high cost and significant environmental impact,particularly in terms of greenhouse gas emissions.To tackle the challenges of sustainable development,there is growing interest in using local available materials with low environmental impact.This study primarily focuses on synthesizing and characterizing a geopolymer binder made from local materials found in Benin to stabilize CEB(compressed earth brick).The synthesis involves combining amorphous aluminosilicate powder with a highly concentrated alkaline solution.Local calcined kaolinite clay(metakaolin)and corn cob ash obtained after calcination at 600°C were used with a 12 M sodium hydroxide(NaOH)solution.Different mixtures of geopolymer were formulated substituting metakaolin by corn cob ash at rates of 0%,5%,10%,and 15%of the dry weight of the mixture.Thereafter physical and mechanical characterization tests were conducted on each formulation.Results showed that geopolymer binders containing 85%metakaolin and 15%corn cob ash exhibited the best physical and mechanical performance(e.g.12.08 MPa for compression strength).Subsequently,this geopolymer formulation was used to stabilize CEB.Characterization revealed that CEBs stabilized with 10%geopolymer exhibit good mechanical properties(6.93 MPa),comparable to those of CEBs stabilized with 10%cement(7.40 MPa),justifying their use as load-bearing walls in construction.