Currently, there is an increasing demand in the development of colorimetric ammonia-responsive smart packaging materials for real-time monitoring of food freshness. Herein, a novel dual-functional Fe-D-Arg (where D-Arg refers to D-arginine) complex nanocrystal with inherent antimicrobial activity and colorimetric ammonia-responsive characteristic was constructed and then incorporated into a cellulose nanocrystal (CNC) matrix to produce high-performance active smart films. The effects of Fe-D-Arg complex on the structural, physical, and functional properties of the CNC films were investigated. The results revealed that the Fe-D-Arg complex nanocrystals were uniformly dispersed within the CNC matrix, thereby markedly improving the film's UV-shielding capability (nearly 100 % efficiency), mechanical strength (55.89 MPa), ductility, hydrophobicity, and water barrier properties. Furthermore, incorporation of the Fe-D-Arg complex endowed the films with long-term color stability and excellent antimicrobial activity (over 95 %) against Escherichia coli and Staphylococcus aureus. The CNC/Fe-D-Arg composite films also possessed favorable colorimetric responsiveness to ammonia. When applied for shrimp freshness monitoring, these composite films showed distinct color changes corresponding to the increasing levels of total volatile basic nitrogen (TVBN). These results suggest that the developed CNC/Fe-D-Arg composite films are promising candidates for use as active and smart food packaging materials.

The utilization of hierarchical porous supports to fabricate an efficient solid catalyst is a feasible strategy due to their remarkable merit in ameliorating the diffusion of reactants on the catalyst surface and increasing the exposure of active species in particular for the bulky molecule-involving reactions. In this research, to abatement the mass transfer resistance of large triglycerides, the hierarchical porous solid catalyst (xAIL@HP UIO-66-NH2) was prepared by grafting acidic ionic liquid (AIL) with double acidic sites of -SO3H and HSO4- onto micro-mesomacroporous metal-organic gels (HP UIO-66-NH2) through acid-base interactions between -NH2 moiety of HP UIO-66-NH2 and acidic moiety of AILs. The catalyst characterization results showed that the xAIL@HP UIO-66NH2 catalyst owned the hierarchical porous structure and double Br & oslash;nsted-Lewis acid centers with large BET surface area and pore volume. This catalyst was adopted for efficient biodiesel production from low-grade acidic oils, exhibiting high catalytic activities for triglyceride transesterification and free fatty acid (FFA) esterification reactions. By using acidic oils as feedstocks, the oil transesterification conversion could reach 91.3 % and the FFAs were completely converted to biodiesel under the conditions of 130 degrees C for 8 h at methanol-to-oil molar ratio of 35: 1 and catalyst dosage of 8 wt%. Based on the kinetic study, the activation energy Ea of this catalyst was 56.6 kJ/ mol, and the reaction complied with pseudo-first-order kinetics. This solid catalyst demonstrated satisfactory acid and water resistance, with good reusable performance, posing great potential in the efficient biodiesel preparation by the one-pot method using the low-grade acidic oils.

Colorimetric ammonia-sensing smart packaging materials that enables real-time visual detection of food freshness play an important role in ensuring food safety. This work involved the construction of a novel Cu/Na-metal organic framework (CuNa-MOF) colorimetric ammonia sensing agent and its subsequent exploitation as functional reinforcing filler of potato starch (PS) substrate to boost the fabrication of high-performance smart packaging materials. Based on single crystal data analysis, a new mechanism of crystal-to-crystal phase transformation was proposed for the colorimetric ammonia-sensing action of CuNa-MOF. This new mechanism involved only minor changes in CuNa-MOF crystal structure (with the coordinated water replaced by ammonia), indicating its unique structural integrity and stability, thus contributing to superior ammonia sensing ability. The results also demonstrated that the introduction of CuNa-MOF (2-6 wt%) within PS substrate resulted in the formation of compatible and tight nanocomposite films. When the content of CuNa-MOF increased from 0 to 6 wt %, the tensile strength, water vapor barrier, and oxygen barrier capability was respectively increased by 11.6 %, 16.4 %, and 18.2 %, and the UV-shielding efficacy was increased from 36.8 % to 96.1 %. Furthermore, the fabricated PS/CuNa-MOF film presented good biocompatibility and long-term colour stability, while combining remarkable colour-changing ammonia sensing function with high antibacterial efficiency (100 %) against Escherichia coli and Staphylococcus aureus. Additionally, the PS/CuNa-MOF film allowed for real-time visual monitoring of prawn freshness decay by discernible coloration changes. This work offers a new strategy in the design of high-performance colorimetric ammonia-sensing materials for smart packaging application.

A new dual-functional Fe-ICA complex nanocrystal featuring intrinsic antioxidant and colorimetric ammoniasensitive functions was designed and then combined with cellulose nanocrystal (CNC) to synergistically fortify potato starch (PS) matrix for developing advanced smart active packaging films. The influence of different FeICA: CNC weight ratios on the structural, physical performances, and functional features of PS film was fully studied. Results revealed that the optimized film (PS/Fe-ICA2/CNC4) demonstrated significantly improved mechanical strength (8.26 MPa), ductility (27.11 %), hydrophobicity (94.6 degrees), and water/oxygen barrier performances, due to the synergistic effect of well-dispersed Fe-ICA/CNC. PS/Fe-ICA/CNC film was also endowed with potent UV-screening, antioxidant efficiency, colorimetric ammonia-sensitivity, long-term color stability, and biocompatibility. Besides, the PS/Fe-ICA/CNC film presented clear color alteration in response to shrimp spoilage, affirming its applicability for visually monitoring shrimp freshness. This work offered a new ammoniasensitive smart packaging strategy by combining functional Fe-based complex and CNC through synergistic effects for freshness monitoring.

A new dual-functional Fe-CIT complex nanocrystal with good antimicrobial effect and colorimetric ammonia-sensitivity was synthesized and then introduced into polyvinyl acetate (PVA) film-forming matrix to construct active smart packaging films with excellent performances. Results revealed that the Fe-CIT complex could form robust hydrogen bonding interaction with PVA film matrix, resulting in an ultra-high tensile ductility (372.81 %). The fabricated Fe-CIT/PVA film also exhibited a significantly improved hydrophobicity (84.3°), UV-blocking efficacy (100 %), and oxygen/water barrier capacity. Furthermore, the Fe-CIT/PVA film possessed outstanding long-term color stability, biocompatibility, antimicrobial activity, and colorimetric ammonia-sensitivity. Application trials confirmed that the Fe-CIT/PVA smart film was capable of effectively monitoring the freshness of shrimp during storage at 4 °C and 25 °C. This work demonstrates that dual-functional Fe-based complex (Fe-CIT) serves as a stable and effective active element, showing promising commercial potential in terms of cost-effectiveness and scalability for the development of advanced smart active packaging materials.

The development of colorimetric ammonia-sensing smart packaging materials with real-time freshness detection ability are crucial for ensuring food safe. This research involved the construction of Cu-based framework (CuPhe) nanorods with colorimetric ammonia-sensing ability through an easy-to-perform aqueous solution method, and their subsequent utilization as nano inclusions in starch/sodium alginate (ST/SA) substrate to foster the creation of high-performance smart packaging materials. Research findings revealed that the addition of Cu-Phe nanorods (3, 6, 9 wt%) within ST/SA substrate led to the formation of compatible nanocomposite films with significantly augmented physical performance and functionality. Especially, the film containing 9 wt% Cu-Phe presented the highest tensile strength (30.32 MPa), elongation at break (19.12 %), UV-shielding efficacy (blocking >99 % of UV passage), water vapor barrier effectiveness (1.90 x 10(-6) g/m & sdot;h & sdot;Pa) and oxygen barrier ability (2.26 x 10(-3) g/m(2)& sdot;s). In addition, the developed ST/SA/Cu-Phe nanocomposite film possessed excellent antibacterial activity (over 99.9 %) against Escherichia coli and Staphylococcus aureus, superior colorimetric ammonia-sensing ability, and long-term colour stability. Also of note, the Cu-Phe added ST/SA nanocomposite film allowed for detecting prawn and pork freshness reduction in real-time via discernible colour transition, suggesting its extensive promise for smart packaging applications.

The catalytic decomposition of methane (CDM) is a plausible means to convert methane to turquoise hydrogen with simultaneous carbon sequestration, in the form of solid carbon nanomaterials (CNMs). The key to a cost-effective CDM process is a high-performance and low-cost catalysts. Mg-Fe-O CDM catalysts have shown outstanding CDM performance in comparison with Fe, whilst being affordable and easy to produce. By optimizing the Fe: Mg ratios (3: 1, 2: 1, 1: 1, 1: 2, 1: 3) of Mg-Fe-O catalysts to render the best activation and exsolution behavior of fresh catalysts containing partial solid solutions. The structural–functional relationships relevant to CDM are established by characterizing the fresh catalysts, the spent catalysts, as well as catalysts sampled at various stages of CDM by using BET, XRD, TEM-EDS, H2-TPR, Raman and TG. The results are interpreted with the help of computationally calculated phase diagrams of the Mg-Fe-O system at the operating conditions of interest. Notably, the catalyst with a Fe: Mg ratio of 1 offers the optimal CDM performance in terms of methane conversion (maximum 48%) and carbon yield (8.6 gC/gFe), attributed to the efficient exsolution of well dispersed Fe0 particles from the MgO-FeO solid solution matrix. As the CDM reaction proceeded, Fe/MgO catalysts gradually become coated with deposited CNMs, ultimately leading to the CDM process cessation. The results exemplify the importance of understanding the redox behavior of solid solutions for designing cost-effective CDM catalysts with superior catalytic performance.

In the realm of food safety, innovative intelligent packaging material that can provide the capacity for timely and effectively monitoring the food freshness are essential. In this work, ammonia-sensitive Cu-based metal organic framework (Cu-LTE) nanocrystal was manufactured and characterized, and then explored as a functional compatibilizer of carboxymethyl starch/polyvinyl alcohol (CMS/PVA) blend to develop novel intelligent packaging film materials. The results demonstrated that the introduction of Cu-LTE nanocrystal into CMS/PVA blend brought about significant promotions regarding to the compatibility, mechanical strength (48.1 MPa), UV-protection (with UV transmittance of only 1.6 %), and moisture/oxygen barrier effectiveness, while preserving long-term colour stability of the blend film. Moreover, the developed CMS/PVA/Cu-LTE blend film featured remarkable antibacterial capacity (over 99.0 %) toward both E. coli and S. aureus bacteria, as well as outstanding colour change ability under ammonia environment. The developed CMS/PVA/Cu-LTE blend film also presented visually identifiable colour change during the monitoring of shrimp deterioration. These findings indicated that the developed CMS/PVA/Cu-LTE blend film should hold tremendous potential as an intelligent active packaging material.

Nowadays, ammonia-responsive biopolymer-based intelligent active films are of great interest for their huge potential in maintaining and monitoring the freshness of seafood. However, it is still a challenge to create biopolymer-based intelligent active films with favorable color stability, antibacterial and visual freshness indication functions. Herein, cobalt-based metal-organic framework (Co-MOF) nanosheets with ammonia-sensitive and antibacterial functions were successfully synthesized and then embedded into carboxymethyl cellulose (CMC) matrix to develop high performance and multifunctional CMC-based intelligent active films. The influence of Co-MOF addition on the structure, physical and functional characters of CMC film was comprehensively studied. The results showed that the Co-MOF nanofillers were homogeneously embedded within the CMC matrix, bringing about remarkable promotion on tensile strength (from 45.3 to 62.2 MPa), toughness (from 0.7 to 2.3 MJ/m3), water barrier and UV-blocking performance of CMC film. Notably, the obtained CMC/Co-MOF nanocomposite films also presented excellent long-term color stability, antibacterial activity (with the bacteriostatic efficiency of 99.6 % and 99.3 % against Escherichia coli and Staphylococcus aureus), and ammonia-sensitive discoloration performance. Finally, the CMC/Co-MOF nanocomposite films were successfully applied for realtime visual monitoring of shrimp freshness. The above results demonstrate that the CMC/Co-MOF nanocomposite films possess huge potential applications in intelligent active packaging.

Nowadays, there is an increasing demand for smart packaging materials capable of effectively monitoring the food freshness. In this study, new Co-based MOF (Co-BIT) microcrystals with ammonia-sensitivity and antibacterial function were constructed and then loaded within cellulose acetate (CA) matrix to create smart active packaging materials. The influences of Co-BIT loading upon structure, physical, and functional properties of the CA films were then thoroughly explored. It was observed that microcrystalline Co-BIT was uniformly integrated inside CA matrix, which caused significant promotions in mechanical strength (from 24.12 to 39.76 MPa), water barrier (from 9.32 x 10(-6) to 2.73 x 10(-6) g/m.h.Pa) and ultraviolet light protection performances of CA film. Additionally, the created CA/Co-BIT films displayed striking antibacterial efficacy (>95.0 % for both Escherichia coli and Staphylococcus aureus), favorable ammonia-sensitivity function as well as color stability. Finally, the CA/Co-BIT films were successfully applied for indicating the spoilage of shrimp through discernible color changes. These findings suggest that Co-BIT loaded CA composite films have great potential for use as smart active packaging.

Biomass materials are high-quality raw materials for the preparation of natural, green and highly active functional materials due to their rich active groups, wide sources and low toxicity. Bagasse xylan (BX) and resveratrol (Res) were used as raw materials to introduce ethylene glycol dimethacrylate (EGDMA) via grafting reaction to obtain the intermediate product BX/Res-g-EGDMA. The intermediate was esterified with 3-carboxyphenylboronic acid (3-CBA) to obtain the target product 3-CBA-BX/Res-g-EGDMA. The BX/Res-composite-modified nanoderivative with antitumor activity was synthesized with the nanoprecipitation method. The effects of the reaction conditions on the grafting rate (G) of BX/Res-g-EGDMA and the degree of substitution (DS) of 3-CBA-BX/Res-g-EGDMA were investigated using single-factor experiments. The results showed that under the optimized process conditions, G and DS reached 142.44% and 0.485, respectively. The product was characterized with FTIR, XRD, TG-FTC, 1H NMR and SEM, and its anticancer activity was simulated and tested. The results showed that 3-CBA-BX/Res-g-EGDMA had a spherical structure with an average particle size of about 100 nm and that its crystalline structure and thermal stability were different from those of the raw materials. In addition, 3-CBA-BX/Res-g-EGDMA showed the best docking activity with 2HE7 with a binding free energy of −6.3 kJ/mol. The inhibition rate of 3-CBA-BX/Res-g-EGDMA on MGC80-3 (gastric cancer cells) reached 36.71 ± 4.93%, which was 18 times higher than that of BX. Therefore, this material could be a potential candidate for biomedical applications.

以木薯淀粉为原料,在氧化木薯淀粉的基础上,以丁二酸酐为酯化剂、对甲苯磺酸为催化剂得到氧化木薯淀粉丁二酸酯(OCSS),进一步以丙烯酸乙酯为接枝单体、过硫酸铵为引发剂得到氧化木薯淀粉丁二酸酯-g-丙烯酸乙酯(OCSS-g-EA).在酯化剂加入量(相对于淀粉干基质量)为100％、酯化时间为3.0 h、酯化温度为35℃、催化剂加入量为3％的条件下,OCSS的酯化取代度可达0.133;在接枝时间为4.0 h、接枝温度为45℃、丙烯酸乙酯与淀粉干基的质量比为1.50:1、引发剂浓度为50 mmol/L的条件下,OCSS-g-EA的接枝率和接枝效率分别可达67.02％和41.93％.OCSS-g-EA的吸油率达84.37％,对污水COD的吸附去除率达75％以上,对Cu2+的吸附量可达19 mg/g,吸附性能优良.

This work explored biodegradable polyvinyl alcohol/starch (PVA/ST) film compatibilized by rod-like ZnO nanofillers as multifunctional food packaging materials. The influence of rod-like ZnO nanofillers on the microstructural, UV-shielding, antibacterial, mechanical, thermal, together with water barrier performances of PVA/ST composite films was fully studied. Results revealed that rod-like ZnO nanofillers could be uniformly distributed into the PVA/ST matrix, playing the role of compatibilizers to provide compact and dense nanocomposite films. The resulting nanocomposite films presented greatly improved mechanical and water vapor barrier properties as compared to virgin PVA/ST film. Moreover, the well distributed ZnO endowed PVA/ST film with excellent antimicrobial activity against both E. coli and S. aureus, together with outstanding UV-shielding capability meanwhile retaining highly optical transparency (approximately 90%). The developed PVA/ST/ZnO films were tested for packaging fresh-cut carrot slices to prevent microbial infection and prolong their shelf life. These results indicated that the developed highly transparent and multifunctional PVA/ST/ZnO nanocomposite films possess broad application prospects in active food packaging field.

As a biocompatible biomaterial, bagasse xylan (BX) has been widely used in the biomedical field. The low biological activity of andrographolide (AD) restricts its development, so AD with certain anticancer activity is introduced. We use chemical modification methods such as grafting and esterification to improve the biological activity and make a novel anticancer nanomaterial. On the basis of the esterification of a mixture of BX and AD with folic acid (FA), a novel anticancer nanoderivative of bagasse xylan/andrographolide folate-g-dimethylaminoethyl methacrylate (DMAEMA)/diethylene glycol dimethacrylate (DEGDMA) nanoparticles (FA-BX/AD-g-DMAEMA/DEGDMA NPs) was synthesized by introducing DMAEMA and DEGDMA monomers through a graft copolymerization and nanoprecipitation method. The effects of reaction temperature, reaction time, the initiator concentration and the mass ratio of FA-BX/AD to mixed monomers on the grafting rate (GR) were investigated. The structure of the obtained product was characterized by FTIR, SEM, XRD and DTG. Further, molecular docking and MTT assays were performed to understand the possible docking sites with the target proteins and the anticancer activity of the product. The results showed that the GR of the obtained product was 79% under the conditions of the initiator concentration 55 mmol/L, m (FA-BX/AD):m (mixed monomer) = 1:2, reaction temperature 50 °C and reaction time 5 h. The inhibition rate of FA-BX/AD-g-DMAEMA/DEGDMA NPs on human lung cancer cells (NCI-H460) can reach 39.77 ± 5.62%, which is about 7.6 times higher than that of BX. Therefore, this material may have potential applications in the development of anticancer drug or carriers and functional materials.

港口起重机的平面度测定是其安全性评估的重要环节之一,针对传统测定方法在工程领域应用的局限性,提出利用近景摄影测量及计算机相关处理技术来解决港口起重机平面度测定问题.近景摄影测量可以获得待测平面大量的点云信息,运用最小二乘法拟合点云坐标形成参考平面,计算参考平面两侧的点到该平面的最大距离之和,完成平面度的计算.实验的结果表明,基于近景摄影测量的起重机平面度测定方法,可以快速精准的完成多台起重机多组数据的测量与处理,工程应用环境要求低,后期处理方便,测量稳定性好.

摄影测量技术作为一种新兴的测量技术,现今被广泛用于工程测量领域.将摄影测量应用于大型工程机械的测量,特别是港口起重机械时,受限于复杂的工作环境和机器本身庞大的体型,通常无法获得良好的拍摄角度和控制点.为克服这些问题,提出一种基于系统自标定的摄影测量方法.将普通数码相机和旋转平台连接,实现相机在空间中的旋转.在实验室内确定相机的旋转参数,正式拍摄时根据相机旋转的角度解算相机在空间中的位置和姿态,无需在港口起重机械上设置控制点.实验结果表明,解算出的待测点相对误差最大为1.84％,满足测量要求.

以蔗渣木聚糖(BX)为主要原料,丙烯酰胺(AM)、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)为接枝单体,过硫酸铵为引发剂,N,N-亚甲基双丙烯酰胺为交联剂,在水溶液中合成了蔗渣木聚糖共聚物BX-g-AM/MMA/BA;再以丁香酸为酯化剂,在N,N-二甲基乙酰胺(DMAC)有机溶剂中进行酯化反应合成蔗渣木聚糖丁香酸酯-g-AM/MMA/BA(BESG3).考察了合成工艺参数对其取代度(DS)的影响.结果表明:在m(催化剂):m(BX-g-AM/MMA/BA)=0.5:2、m(丁香酸):m(BX-g-AM/MMA/BA)=0.95:2、75℃下恒温反应9.5h时,产物蔗渣木聚糖丁香酸酯-g-AM/MMA/BA(BESG3)的DS为1.074.采用FTIR、1H NMR、XRD、SEM和TG-DTG对BX和BES G3的结构进行了表征.通过分子动力学对BES G3与癌蛋白进行了对接活性模拟,并采用溴化噻唑蓝四氮唑(MTT)法对产物进行了抗癌活性测试,其对肺癌细胞的抑制率达33.47％.

在充分地分析了岸边桥式集装箱起重机金属结构的评价指标后,根据岸边集装箱起重机寿命指标的特点,提出了基于寿命的评价方法,并使用12台岸边集装箱起重机的检测数据与寿命评价数据对LM-BP神经网络进行训练,得到了岸边集装箱起重机的安全评价模型,最后将神经网络得到的结果与模糊层次分析法的结果进行对比,证明了方法的可行性.

近景摄影测量作为一种新的技术手段,如今已逐渐被广泛应用于工程领域.港口起重机由于自身的庞大结构,外形尺寸的测量难度大,而起重机的安全性评估又与相关尺寸有密切联系.为解决这一问题,构建了一个无控制点的起重机近景摄影测量模型.通过设定坐标系系统,利用相关算法处理像片得到待测点坐标.实验的结果表明,基于测量系统内部坐标系的起重机械无控制点的测量方法,不需要在物方空间标定控制点,也可以获得物方点坐标,且测量精度较好.该方法是在起重机复杂的应用场景下对相关尺寸进行测量的一种新的实用手段.

输送带跑偏检测技术在矿山、港口以及电力等行业中有着举足轻重的地位,但是目前尚没有一种能够准确、实时地对输送带位置、运行状态进行检测的技术.颜色识别作为一种准确、可靠、高效的检测技术,是输送带跑偏检测的理想选择.对此,本文提出一种基于颜色检测的输送带跑偏检测技术,通过视频监控屏幕上的刻度来检测输送带跑偏程度,同时根据输送带上色带颜色变化判断输送带拉伸程度和应力状态.