查找使用阿拉丁产品的科研文献

Synthesis and characterization of a guar gum-based flocculant and its flocculation-dewatering mechanism in coal mine wastewater

Na Li,Yuping Fan,Xianshu Dong,Xiaomin Ma,Ruxia Chen,Ming Chang,Guang Xu

To enhance coal utilization efficiency and improve the dewatering performance of flocculants, the hydrophobic cationic monomer benzyl (methacryloyloxyethyl) dimethylammonium chloride and guar gum was utilized to synthesize a guar gum grafted polymethacryloyloxyethyl benzyl ammonium chloride flocculants (GG-g-BMDAC), and the polymerization conditions were optimized: GG concentration of 1.5 %, BMDAC/GG ratio of 1:10, photoinitiator concentration of 0.3 %, irradiation time of 90 min, weakly acidic pH, and urea addition when the viscosity of the system is too high. Comprehensive characterization of the GG-g-BMDAC flocculant was conducted through various analytical techniques including FTIR, XPS, NMR, XRD, SEM, and TG-DSC. Flocculation-dewatering tests demonstrated that GG-g-BMDAC significantly enhanced the clarity and dewatering speed of coal mine wastewater, and the optimal dosage of GG-g-BMDAC was 1.2 mg/g (s) : sedimentation speed reached 2.58 cm/min, transmittance is 81.10 %, deposit thickness is 10.80 cm, dewatering speed is 138.74 cm/h, filter cake moisture is 36.25 %, and average mass specific resistance is 11.26 m/kg·10 11 . Zeta potential measurements, adsorption analysis, and wettability testing indicated that GG-g-BMDAC exhibited strong charge neutralization, bridging effects, and hydrophobic interactions. This study provides valuable insights for preparing the environment friendly flocculant with high dewatering efficiency in industrial wastewater treatment applications.

Effects of guar gum/chitosan edible films functionalized with citronellal/HPβCD inclusion complex on Harbin red sausage preservation

Ce Shi,Li Jia,Hongxun Tao,Changzhu Li,Tariq Aziz,Majid Alhomrani,Haiying Cui,Lin Lin

Harbin red sausage is a traditional local pork meat product in China, but it is susceptible to microbial contamination and lipid oxidation, leading to quality deterioration. Herein, guar gum (GG)/chitosan (CS) edible films functionalized with citronellal/hydroxypropyl- β -cyclodextrin inclusion complex (CIT/HP β CD-IC) were fabricated for Harbin red sausage preservation. Results demonstrated CIT/HP β CD-IC was successfully prepared and observed by SEM due to the bathochromic shift of maximum absorption peak of CIT, and the formation of new bonds was confirmed by FTIR analysis, suggesting the embedding of CIT into HP β CD cavity. The changes of functional groups stretching vibrations suggested successful loading of CIT/HP β CD-IC into the GG/CS edible films. Furthermore, the incorporation of CIT/HP β CD-IC enhanced the microstructural, mechanical and barrier properties, and improved the antibacterial activities, biodegradability and thermal stability of the GG/CS edible films. Particularly, the GG/CS edible films incorporated with 1 % CIT/HP β CD-IC (GG/CS-IC 1 %) enhanced the storage stability of Harbin red sausage at 4 °C by decreasing the weight loss rate, maintaining the pH, color, and textural stabilities, retarding the microbial growth and lipid oxidation of the sausage samples. Findings here suggested that GG/CS-IC 1 % edible films showed great potential as novel multi-functional edible packaging materials for Harbin red sausage preservation.

Fabrication of anti-freezing and self-healing hydrogel sensors based on carboxymethyl guar gum and poly(ionic liquid)

Shu He,Hongli Fang,Jia Liu,Xing Wu,Zeng Liu,Wen Gu,Wei Shao

As classical soft materials, conductive hydrogels have attracted wide attention in the field of strain sensors due to their unique flexibility and conductivity. However, there are still challenges in developing conductive hydrogels with comprehensive mechanical strength, self-healing ability and sensitive sensing properties. In this paper, a novel PAV/CMGG hydrogel was prepared by a simple one-pot method through the introduction of 1-vinyl-3-butylimidazolium bromide (VBIMBr), acrylic acid (AA), carboxymethyl guar gum (CMGG) and AlCl 3 . The coordination bond between Al 3+ and –COO − groups on PAA and CMGG, the hydrogen bond between PAA and CMGG, and the electrostatic interaction between [VBIM] + and –COO − endow the hydrogel with good mechanical properties, self-recovery ability, fatigue resistance and great self-healing properties. PAV/CMGG hydrogel had good conductivity of 2.31 S/m which could successfully light up the bulb. The hydrogel as the strain sensor had not only a wide strain sensing capability (strain ranging from 0 to 800 %), but also a high strain sensitivity (gauge factor (GF) = 28.50 for the strain ranging from 600 to 800 %). This study can provide inspiration for the construction of new high-performance flexible sensors.

Enzymatic conversion of guar gum to prebiotic mannooligosaccharide by efficient β-mannanase FsMan26 and unveiling its hydrolytic properties

Lingli Zhong,Ying Wang,Kai Yang,Wenming Chang,Xue Gao,Manqi Peng,Xianfeng Ye,Yanling Ji,Yiting Jing,Jie Bai,Lei Zhang,Zhengguang Zhang,Yan Huang,Zhongli Cui,Zhoukun Li

A novel GH26 β-mannanase ( Fs Man26) from Fibrobacter succinogenes was expressed in Bacillus subtilis. • Fs Man26 specifically hydrolyzed galactomannan and glucomannan through an endo-acting mechanism, yielding a heterogeneous mixture of mannooligosaccharides (MOS) with diverse chain lengths and structures. • Fs Man26 efficiently converted high-concentration (20-30%) food-grade guar gum into MOS. • Guar gum hydrolysate (F-GGH) prepared by Fs Man26 contained 85.5% MOS (predominantly DP2-7), with a total MOS yield of 77.3%. • F-GGH exhibited dual functional properties by selectively stimulating probiotic growth and effectively adsorbing mycotoxins. Mannan-rich polysaccharides such as guar gum represent important renewable substrates to produce functional mannooligosaccharides (MOS) with prebiotic potential. In this study, an efficient β-1,4-mannanase Fs Man26, from Fibrobacter succinogenes S85 was identified and expressed in Bacillus subtilis . Fs Man26 demonstrated high specificity toward galactomannans and glucomannans and cleaved various mannans into MOS with varying degree of polymerization (DP). Under optimized conditions, Fs Man26 efficiently hydrolyzed high-concentration (20-30%) food-grade guar gum, achieving over 85% degradation within 8 h. Guar gum hydrolysate (F-GGH) prepared by Fs Man26 contained 85.5% MOS, and the proportion of DP2-7 oligosaccharides in MOS was 83.0%. In vitro evaluation revealed that F-GGH promotes the growth of probiotic strains such as Lactobacillus plantarum and Bacillus subtilis , but inhibits the growth of pathogenic bacteria. Moreover, F-GGH exhibited higher adsorption capacity for deoxynivalenol compared to commercial prebiotics. These findings highlight Fs Man26 as a promising biocatalyst for industrial-scale production of prebiotic MOS that suitable for food and feed applications.

Development and Performance Evaluation of the Nanoparticle-Enhanced Seawater-Based High-Temperature-Resistant Guar Gum Fracturing Fluid System

Xin Li,Mingwei Zhao,Huan Zhang,Lixiao Zhang,Ruiqiong Liu,Xinjie Xu,Zhenfeng Ma,Zhongzheng Xu,Caili Dai

Abstract To address the problems of low viscosity retention, and insufficient sand-carrying capacity for seawater-based fracturing fluids in deepwater high-temperature reservoirs, this study enhanced the fracturing fluid by adding modified nano-SiO2 (M-NS). A seawater-based, high-temperature-resistant fracturing fluid system was constructed from M-NS and carboxymethyl hydroxypropyl guar gum (CMHPG). The results showed that 3-aminopropyltriethoxysilane (APTES) modification improved, to a certain extent, the dispersion stability and interfacial compatibility of nano-SiO2 (NS) in the seawater-based CMHPG solution. The optimal formulation of the M-NS-enhanced system was 0.4 wt % CMHPG, 0.5 wt % organic zirconium crosslinker, 0.08 wt % M-NS, 0.1 wt % APS, and 0.05 wt % SDS. After shearing at 200 °C and 100 s–1 for 2 h, the retained viscosity was 60.03 mPa·s, which was 1.42 times that of the conventional system. At 95 °C, no proppant settling was observed at sand ratios of 10%, 20%, and 30%. In addition, the fracturing fluid exhibited favorable breaking and flowback performance, dynamic leak off control performance, and formation-damage performance. Investigation of the high-temperature-resistance mechanism revealed that the M-NS-enhanced fracturing fluid system demonstrated excellent viscosity recovery and nonlinear elastic response under large strain. This improvement is attributed to the formation of physical crosslinking through hydrogen bonding between the −NH2 on the M-NS surface and the hydroxyl and carboxymethyl groups on the polymer chains. This physical crosslinking mechanism likely synergizes with the organic zirconium chemical crosslinking to construct a dual-network structure. Moreover, M-NS is uniformly dispersed in the CMHPG base fluid, acting as rigid nucleation points and a skeleton. Consequently, the network skeleton of the enhanced gel is significantly thickened, and the structure of the gel is enhanced. This study provides a seawater-based, high-temperature-resistant guar gum fracturing fluid system for deepwater and ultra-deepwater high-temperature reservoirs, demonstrating significant engineering application potential.

Design and Synthesis of Hydrogels Dressings Made with Guar Gum to Enhance Antimicrobial and Skin Wound Healing Properties

Bo Feng,Wenwen Kang,Chunyan Liu

Background The skin is the largest organ of the human body and serves as its natural barrier. Trauma to the skin can lead to bleeding or infection, potentially resulting in shock or even death. Conventional gauze lacks antimicrobial properties and mobility, making it ineffective in treating skin wounds. Hydrogels, due to their excellent biocompatibility and softness, are considered ideal wound dressings. Methods Hydrogels dressings based on cationic guar gum (CGG) were constructed using (4-hydroxyphenylboronic acid) cysteamine as a crosslinker. The structure and morphology of the CGG hydrogels were characterized using scanning electron microscopy (SEM). Furthermore, experiments including in vitro antimicrobial testing, CCK-8 assays, live/dead cell staining, and animal model wound healing were conducted to evaluate the antimicrobial activity, safety, and wound healing efficiency of CGG hydrogels. Results The prepared CGG hydrogel exhibited a three-dimensional mesh structure. In vitro antimicrobial, CCK-8, and live/dead cell staining experiments demonstrated that the CGG hydrogel effectively inhibited the growth of Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ) while showing no significant toxicity to human skin fibroblast cells (CCD-986sk), indicating good biocompatibility. Moreover, results from animal model wound healing experiments indicated that the CGG hydrogels possessed a notable ability to promote wound healing. Conclusion CGG hydrogels effectively inhibited bacterial growth and promoted wound healing, making them safe and efficient dressings for skin wound treatment.

Tuning stability and thermal rheology properties of the fluorine-free foams co-stabilized by guar gum and surfactants

Youjie Sheng,Tiantian Wang,Yang Li,Li Ma,Qian Zhao,Baohu Li

The development of highly stable and environmentally friendly foams is of utmost urgency. This study systematically investigated the effects of temperature on the viscosity and viscoelasticity of fluorine-free foams stabilized by guar gum (GG), silicon, and hydrocarbon surfactants. The experiment investigated the surface properties and foaming ability of various hydrocarbon surfactants, and selected the excellent BS-12 and the silicone surfactant LS-408L for compound use. The research found that the viscosity of the LS-408L/BS-12 solution increased as the concentration of GG increased. Among them, when the concentration of GG was 0.2wt%, the foam exhibited excellent stability. The rheological tests demonstrated that both the LS-408L/BS-12/GG stabilized foam solution and the foam exhibited the non-Newtonian fluid characteristics of shear thinning. As the temperature rises, the viscosity and viscoelasticity of the solution and the foam continue to decrease. It is notable that when the temperature reaches 67 °C, the loss factor (tan δ) is much greater than 1, indicating that the foam exhibits a significant dominant viscous behavior. Moreover, when the temperature reached 80 °C, the foam drainage accelerated, and the drained liquid exhibited a dynamic elastic response structure under the effect of high temperature. This study provides key data support for the optimized design of fluorine-free foam materials and has guiding significance for their application in different temperature environments.

A novel polyvinyl alcohol/guar gum hydrogel-based fluid abrasive for abrasive flow machining with enhanced processing performance

Jingyi Liu,Xiaoyun Bai,Wenhui Li,Xiuhong Li,Xiaoming Yin,Shengqiang Yang,Kun Li

Selective laser melting (SLM)-fabricated components often exhibit high surface roughness and inherent surface defects, necessitating efficient post-processing. Hydrogel-based fluid abrasives are environmentally friendly alternatives for abrasive flow machining (AFM). However, traditional hydrogel matrices are generally based on polysaccharide polymers and suffer from limited mechanical strength and poor thermal stability, leading to water loss during processing, which restricts their practical application. To overcome these limitations, this study develops a novel polyvinyl alcohol-guar gum (PVA-GG) hydrogel-based fluid abrasive for the AFM of SLM-fabricated surfaces. In this system, the PVA provides mechanical load-bearing capacity, while the GG enhances viscoelasticity, jointly forming a tightly entangled network structure. The fluid abrasive was systematically characterized in terms of viscoelasticity, self-healing properties, thermal stability, and degradability, and its process performance was evaluated during the finishing of SLM-fabricated GH4169 alloy flow channels. The PVA-GG fluid abrasive shows significantly higher viscosity and modulus, with a weight loss of only 9.09 % below 100 °C. It also demonstrates remarkable self-healing properties and degradability. After AFM processing, the surface roughness ( Ra ) of the workpiece can be reduced by 90 %, and the material removal rate ( MRR ) reaches 0.43 mm³ /min, outperforming conventional fluid abrasives. Material removal in PVA-GG fluid abrasive is achieved through the combined actions of sliding, plowing, and micro-cutting. This study provides an efficient, sustainable, and mechanism-based approach for the precision surface finishing of SLM-fabricated components.

Eco-friendly, cost-effective, and durable guar gum/citric acid complex coating on mesh for oil/water separation

Ziru Ye,Kaibing Huang,Mei Xie,Han Yu,Fan Yang,Mingqi Gao,Ruina Wang,Lei Han,Fenxia Wu

Development of active packaging with chitosan, guar gum and watermelon rind extract: Characterization, application and performance improvement mechanism

Fenghui Wang,Cancan Xie,Rong Ye,Hongjie Tang,Longwei Jiang,Yingzhu Liu

The objective of this study was to make a film matrix containing chitosan (CS) and guar gum (GG), and to improve the physicochemical properties of the film using watermelon rind extract (WRE) as a cross-linker and active substance for the preservation of fresh-cut bananas. The results of Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy showed that the WRE and CG matrix formed intermolecular hydrogen bond interactions, which made the structure of the resulting films more compact. With increasing amounts of WRE, the mechanical properties of the films were significantly increased, but the permeability of water vapor and oxygen was significantly decreased ( p  < 0.05). Notably, when the amount of extract reached 4 wt%, the DPPH radical scavenging activity of the composite film significantly increased to 83.24 %, and the antibacterial activity also reached its highest value. Fresh-cut bananas were stored at room temperature with polyethylene film, CG and CG-WRE. The CG with 4 wt% WRE effectively inhibited the changes in appearance, firmness, weight, color and total soluble solids content of fresh-cut bananas during storage. Therefore, CG-WRE as a novel active food packaging material, has good physicochemical properties and great potential to extend the shelf life of foods.

Yin-Yang heat flow rate converter: Based on Guar Gum composite phase change materials with controllable thermal conductivity

Jianfeng Hu,Sixing Zhang,Heqing Fu,Jinqing Qu,Zhengguo Zhang

Solid-liquid phase change materials (PCMs) have broad potential but suffer from leakage problems and unreasonable thermal conductivity, resulting in low utilization efficiency. In this study, using Guar Gum (GG) as large frame and graphene oxide (GO) or SiO 2 aerogel microchip as small frame, thermal conductivity strengthening PCMs (GG-C-PEG) and thermal conductivity weakening PCMs (GG-I-PEG) were prepared after loading polyethylene glycol (PEG). In-depth characterizations turned out that the phase change enthalpy retention was close to 100% of PEG . In particular, the composites achieved 0.94 W/(m·K) of enhanced thermal conductivity and exhibited a reduced thermal conductivity of 0.11 W/(m·K). Simultaneously, the mass of the PCMs remained above 94.08% when heated at 80 °C for 45 min and the loss of melting enthalpy was less than 6.11% after 100 cycles, indicating outstanding stability in shape and performance during the heating–cooling cycles. To further utilize of solar energy, GG-C-PEG exhibited great photothermal conversion efficiency reaching 83.67%. Moreover, inspired by Tai Chi culture, a novel device that could control the heat flow rate from minimum to maximum by utilizing different thermal conductivity properties of the two types of PCMs was designed, taking composite PCMs further into practical scenarios.

A novel high water-soluble antibacterial films-based guar gum incorporated with Aloe vera gel and ε-polylysine

Yakun Zhao,Huan Li,Jian Chen,Yanbo Wang

The high water-soluble films are commonly used in food coating and food encapsulation. In this study, the effect of Aloe vera gel (AV) and ε-polylysine (ε-PL) on the comprehensive properties of films based on guar gum (GG) were investigated. When GG to AV was 8:2, the GG:AV:ε-PL composite films (water solubility = 68.50%) had an 82.42% higher water solubility than pure guar gum (PGG) films (water solubility = 37.55%). Compared with PGG films, the composite films more transparent, better thermal stability and elongation at break. X-ray diffraction and SEM analysis showed the composite films were amorphous structures and the AV and ε-PL did not change the structure of PGG. FITR analysis confirmed the formation of hydrogen bonds within the composite films. Antibacterial properties showed the composite films had a good antibacterial effect against Escherichia coli and Staphylococcus aureus . Therefore, the composite films can be a new option of high water-soluble antibacterial food packaging materials.