Inorganic Chemistry Frontiers
·
2021
·Vol. 9
·期 2
·370-378
·
IF 6.569
Yongyang Zhu,Hao Zhong,Liuzhang Ouyang,Jiangwen Liu,Hui Wang,Huaiyu Shao,Min Zhu
In this work, we reported an energy-saving and cost-efficient process for the (re)generation of NaBH4 by ball milling hydrated borax (Na2B4O7·10H2O) with a Mg–Al alloy under ambient conditions. The introduction of abundant and readily available Al can increase air stability of the reducing agent. A high yield up to 85.2% could be achieved by using Mg17Al12 because of its hardness and brittleness.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2016
·
IF 5.267
Beili Lu,Fengcai Lin,Xin Jiang,Jiajia Cheng,Qilin Lu,Jianbin Song,Chong Chen,Biao Huang
A facile, environmentally benign approach has been developed for the preparation of dynamic, multiresponsive, and self-healing hydrogels from inexpensive bamboo pulp, poly(vinyl alcohol) (PVA), and borax. The microfibrillated cellulose (MFC) reinforced PVA–borax hydrogels were produced through a one-pot route in conjunction with ball milling and physical blending in tandem in aqueous medium. In this way, MFC particles could be efficiently generated and well-dispersed in a polymer matrix, and they have been verified by scanning electron microscopy. The rheology analysis indicated a close relationship between the mechanical strength and the MFC loading and ball milling time. Due to the dynamic equilibrium of the didiol–borax linkages and the reinforcement of MFC fibers, the hydrogels showed enhanced self-healing behavior and mechanical stiffness, which was also supported by rheology analyses. In addition, the hydrogels were found to be sensitive to the pH value. The hydrogels present a solvent or gel state with the change of pH value, and this sol–gel transfer can be repeated while maintaining the shape, further demonstrating the dynamic reversible behavior of the hydrogels.
研究领域:
材料科学
·
生物材料
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2019
·Vol. 6
·期 6
·065615
·
IF 1.449
Miao Liang,Jing Wang,Min Zhao,Jiaxiao Cai,Mingjian Zhang,Nan Deng,Bing Wang,Bin Li,Ke Zhang
A modified hydrothermal carbonization (HTC) process in the presence of borax was developed to produce uniform and monodispersed micro-carbon spheres. Corn starch was used as carbon precursor and borax acts as a structure directing agent. The introduction of borax could catalytically transform the starch into hydroxymethylfurfural (HMF) and favoring the rapid nucleation and slow growth of particle owing to the buffer function of borax additive. The inclusion of borax thus allowed for the controlling of particles morphology as well as tailoring the particle diameters. Uniform solid carbon spheres with a narrow particle size distribution, ranging from 0.6 to 2 μm, was demonstrated by turning the borax concentration and the reaction time in a single-step hydrothermal process. The retained boron content and chemical structure of the carbonaceous products could be adjusted as revealed by inductively coupled plasma (ICP) and Fourier transformed infrared (FTIR) analysis. Furthermore, the boron-dopant increased the final product's thermostability from 536 °C to 629 °C at 0.70 wt% boron content. This method therefore also provides a facile and novel approach to prepare boron-doped carbon materials.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Haixin Zhu,Jun Zeng,Shanshan Jiang,Suning Huang,Zicheng Xie,Yuewen Huang,Shudong Lin,Bin Wang
The increasing prevalence of electronic devices has led to a notable rise in the severity of electromagnetic interference (EMI). Nanofillers in conventional EMI shielding materials aggregate in the matrix, affecting their usability. Hence, with the aim of optimizing the dispersion of silver nanowires (AgNWs) within the matrix and augmenting its conductivity, we herein report a method for modifying silver nanowires and conduct an exhaustive investigation into its practical implementation and performance. An ultra-long aspect ratio AgNWs with an average length of 150.23 μm, an average diameter of 129.82 nm, and an aspect ratio of about 1157 was prepared. Surface hydroxylated silver nanowires (M-AgNWs) were obtained by bis(2-hydroxyethyl) disulfide modification. Polyvinyl alcohol (PVA) and borax hydrogel systems were prepared by the addition of M-AgNWs, resulting in the formation of PVA/Borax/M-AgNWs hydrogels (PB/M-AgNWs). The tensile strength of the self-healing PB/M-AgNWs (0.1 %) hydrogel was able to reach 78 % of the original value. The PB/M-AgNWs (0.2 %) hydrogel, with a conductivity of 3.59 S/m, exhibited a conductivity of 3.09 S/m following self-healing at room temperature, with an estimated self-healing efficiency of 86 %. The hydrogel EMI shielding effectiveness of 2 mm PB/M-AgNWs (0.1 %) is 32.03 dB. 8 mm PB/M-AgNWs (0.1 %) hydrogel has an EMI shielding effectiveness of 65.10 dB, which is 99.9999 % attenuation of the incident electromagnetic waves (EMW).
研究领域:
材料科学
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纳米技术
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电子工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2021
·Vol. 101
·期 1
·103-113
·
IF 2.326
Wang Chen,Shen Zhifeng,Hu Pengfei,Wang Tao,Zhang Xing,Liang Lidong,Bai Jianguang,Qiu Liewei,Lai Xiaojuan,Yang Xiaowu,Zhang Kang
Borax-PVA hydrogels with excellent mechanical properties are prepared by simple physical mixing of polyvinyl alcohol (PVA, thickener) and borax (cross-linking agent) at room temperature. The resulting hydrogel is a three-dimensional structure composed of boric ester bonds as physical crosslinking points. Thus, the spatial structure, swelling properties, viscoelastic properties, tensile properties, and self-healing properties of hydrogels with different ratios of borax and PVA are studied. XRD confirmed that the hydrogels have similar structures near 2 θ values of 10 and 20. The microstructure of the hydrogel is confirmed by SEM and TEM. With an increase of borax mass fraction, the pore structure and morphology of hydrogel are more ordered, with substantial quantities of water immobilized within their three-dimensional structure. The viscoelastic properties and tensile properties showed that when the mass fraction of borax is 5%, the storage modulus and compressive stress of the hydrogel are the highest, reaching 100 Pa and 5.6 kPa, respectively. In addition, through physical and chemical stimulation (heating and varying pH, respectively), the hydrogels also showed reversible gel–sol conversion characteristics, indicating that the boric ester bonds have self-healing properties.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Min Zhang,Feng Deng,Lele Tang,Hui Wu,Yonghao Ni,Lihui Chen,Liulian Huang,Xiaoqing Hu,Shan Lin,Cuicui Ding
Collagen-based hydrogels have been regarded as one of the most popular biomaterials for applications in biomedical engineering as scaffolds, cell or drug carriers and medical implants. Despite numerous studies on collagen-based hydrogels, their applications are still extremely limited due to lack of multi-functionalities. Herein, we present a facile method to prepare a multifunctional, extremely soft collagen-based hydrogel via the introduction of collagen (COL), guar gum (GG), poly(N-isopropylacrylamide) (PNIPAM), graphene oxide (GO) and borax through the formation of both reversible and permanent networks. The resultant hydrogels (COL–GG–PNIPAMs) exhibited desirable properties, including processability, injectability and remoldability. Remarkably, the COL–GG–PNIPAMs stretched manually up to 50 times their initial length before rupturing (from 2 to 100 cm), indicating their super-ductile deformation; when cut, the hydrogels self-healed within a short time period (less than 3 min) without any external stimuli. In addition, the COL–GG–PNIPAMs showed excellent thermal sensitivity and NIR-responsive properties. The potential application of ionic conductive COL–GG–PNIPAMs for strain sensing was also tested by monitoring real-time large-scale movements of the human body or facial micro-expressions. Moreover, the COL–GG–PNIPAMs exhibited a healing ratio of 81.0% for mouse skin wounds, which was higher than that of the blank group (63.6%), demonstrating an enhanced skin wound repair effect. These prominent features of COL-GG-PNIPAMs will broaden versatile collagen-based hydrogels for a variety of applications.
研究领域:
生物医学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 1
·251
·
IF 4.2
Qiulin Li,Yawen Yang,Qingfeng Wang,Xiang Han,Junfeng Zhu,Nan Zhang,Qiuhong Wang,Kanshe Li,Pin Gong,Fuxin Chen
This article applies nuclear magnetic resonance technology to the study of boron-containing traditional Chinese medicine, in order to explore the morphological evolution of boron elements in traditional Chinese medicine. Borax is a traditional Chinese medicine with anti-corrosion, anti-inflammatory, antibacterial, and anticonvulsant effects. It is made by boiling, removing stones, and drying borax minerals like borate salts. This article introduces an11B nuclear magnetic resonance method for identifying and characterizing boron-containing compounds in TCM. We applied this technology to borax aqueous solutions in different chemical environments and found that with boron mixed in the form of SP2hybridization in equilateral triangles and SP3hybridization in equilateral tetrahedra, the pH changes in alkaline environments significantly affected the ratio of the two. At the same time, it was found that in addition to the raw material peak, boron signals of other boron-containing compounds were also detected in 20 commercially available boron-containing TCM preparations. These new boron-containing compounds may be true pharmaceutical active ingredients, and adding them directly to the formula can improve quality and safety. This article describes the detection of11B NMR in boron-containing traditional Chinese medicine preparations. It is simple, non-destructive, and can provide chemical fingerprint studies for boron-containing traditional Chinese medicine.
研究领域:
药学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Junjiao Li,Chao Sui,Chenxi Zhao,Gong Cheng,Zifu Zang,Lei Wen,Yuna Sang,Yichen Zhou,Yushun Zhao,Xin Yan,Xiaodong He,Chao Wang
In recent years, there has been a growing interest in fireproof nanomaterials due to their broad applications in fire-safety and environmental preservation. In this study, one kind of lightweight fireproof hybrid aerogel with low thermal conductivity (0.039 W/m•K) was prepared through a facile ice template method, where the graphene nanosheets and hydroxyethyl cellulose (HEC) are combined with borax crosslinkers. It was found that this aerogel can be not only recyclable and repairable, but also possesses excellent compressive strength and stiffness, owing to the interfacial van der Waals adsorption, ionic crosslinking and hydrogen bonding interactions. Remarkably, it has excellent flame retardancy performance (an extremely low peak heat release rate (PHRR) was measured to be 37.44 kW/m 2 , reduced by 88.6 % comparing to that of graphene/HEC aerogel). To further explore the fire resistance mechanism of this aerogel, the molecular dynamics simulation was performed. It reveals that the borax can effectively wrap and hinder the graphene and HEC molecules from decomposition. Besides, the borax can compact graphene and HEC closer, thereby further isolating heat and oxygen, realizing the fireproof property. This study offers valuable insights for designing advanced fireproof nanomaterials and applications in shipbuilding or construction.
研究领域:
材料科学
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纳米技术
·
火灾安全工程
✓ 已验证
产品关联
DOI
高影响因子
Materials Research Express
·
2019
·Vol. 6
·期 12
·125340
·
IF 1.449
Xi Yang,Meiling Guo,Yuanpeng Wu,Shishan Xue,Yuanmeng Xia,Rui Zhang,Hang Wang,Qipeng Guo
To improve the mechanical strength and realize more functionality of self−healing hydrogels in a cost−effective way, commercially available poly(vinyl alcohol) (PVA), borax and carboxyl methyl cellulose (CMC) were used in this work to prepare polymer hydrogels in one pot. The results show that the as−prepared hydrogels have enhancing strength, self−healing and multi−responsive shape memory properties. The rigid ring of CMC and the cross−linked networks formed by borate ester bonds and hydrogen bonds from PVA, CMC and borax can enhance the strength of the hydrogels, when the mass ratio of PVA/borax/CMC is 10:6:3, the tensile stress can reach up to 0.72 MPa. Borate ester bonds and hydrogen bonds can endow the hydrogels with good self−healing capability, the best self−healing efficiency can reach up to 83%. Additionally, since borate ester bonds are response to pH, and CMC is sensitive to Al3+ and Fe3+, shape memory properties of the hydrogels can be realized by controlling pH, and metal ions.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2024
·
IF 7.4
Zhendong Liu,Longguan Zhu,Bingjian Zhang
Due to natural erosion and human interference, limestone artifacts often suffer from cracks and gradual detachment. There is a critical need for new bonding materials that possess excellent aging resistance and high compatibility with the artifact substrates. This study investigates the effects of varying proportions of citric acid (CA) and borax (B) as composite retarders on the fundamental properties of magnesium phosphate cement (MPC). Through the application of X-ray diffraction techniques and cold field emission scanning electron microscopy, this research elucidates the mechanisms by which the retarders affect MPC. It was found that a 5 % addition of CA and B significantly reduces the hydration temperature during the early stages of MPC setting, enhances the unconfined compressive strength (reaching 44.3 MPa at 28 days), and allows for controllable setting times (17 minutes). Additionally, the presence of CA was found to delay crystal growth, resulting in an increased quantity of the amorphous phase and higher density of MPC. The optimal MPC formulation was selected as a bonding and repair material for limestone artifacts. For comparative analysis, traditional glutinous rice lime mortar (GL) and commercially available epoxy resin (EP) were tested under wet-dry cycling and UV aging conditions. Results indicated that EP materials demonstrated significant aesthetic incompatibilities and progressive cracking and detachment as aging tests progressed. GL materials exhibited significantly lower bonding strength compared to EP and MPC. In contrast, MPC displayed excellent aging resistance, moderate bonding strength, and a Shore hardness value closely matching that of the limestone substrates. Therefore, high-strength, rapid-hardening MPC represents a valuable and forward-looking solution for the conservation of limestone artifacts.
研究领域:
材料科学
·
文物保护
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2024
·
IF 10.7
Shuhao Jiao,Xuefei Yang,Xuejing Zheng,Ying Pei,Jie Liu,Keyong Tang
The present work investigates the effects of nano-chitin with different charge, obtained by acid hydrolysis and TEMPO oxidation , on the structure and properties of borax crosslinked polyvinyl alcohol (PVA) hydrogels. In detail, nano-chitin prepared by acid hydrolysis (ACh) is positively charged (+28.8 mV). The electrostatic attraction between ACh and borax ions leads to a maximum tensile stress of composite hydrogel (ACh/PB), 54.25 KPa, 17 times of the borax crosslinked PVA (PB). In contrast, nano-chitin prepared by TEMPO-oxidation (TCh) shows negative charge (−59.0 mV). Due to the electrostatic repulsion with borax ions, the maximum tensile stress of composite hydrogel (TCh/PB) is only 9.25 KPa, a very limit reinforcing effect. However, TCh/PB showed better self-healing efficiency (96.0 %) as well as ionic conductivity (1.25 × 10 −5 S/m). The present work shows that the charge state of the nano-chitin exerts great influence on the interaction with the crosslinking agent borax, therefore, affects the structure and properties of the final PVA composite hydrogels. The results could provide important information about making full use of nano-chitin as a reinforcement by adjusting its surface charge state.
研究领域:
材料科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2020
·
IF 7.632
Yongyang Zhu,Liuzhang Ouyang,Hao Zhong,Jiangwen Liu,Hui Wang,Huaiyu Shao,Zhenguo Huang,Min Zhu
Sodium borohydride (NaBH4) has been identified as one of the most promising hydrogen storage materials; however, it is still challenging to produce NaBH4 with low cost and high efficiency, which are largely determined by the sources of boron and hydrogen and reducing agents used. Herein, we report an economical method to produce NaBH4 by ball milling hydrated borax (Na2B4O7·10H2O and/or Na2B4O7·5H2O) with different reducing agents such as MgH2, Mg, and NaH under ambient conditions. The direct use of natural hydrated borax avoids the dehydration process (at 600 °C) and consequently reduces cost and improves overall energy efficiency. A high yield of 93.1% can be achieved for a short ball mill duration (3.5 h) for Na2B4O7·5H2O-NaH-MgH2 system. In this system, H2 is generated in situ which subsequently reacts with Mg forming MgH2. Low cost Mg is therefore employed to replace the majority of MgH2, leading to an attractive yield of 78.6%. To further reduce the cost of raw materials and improve the utilization of hydrogen source in the hydrated borax, Na2B4O7·10H2O is used to partially substitute for Na2B4O7·5H2O, leading to a complete replacement of MgH2. Compared with literature results, the optimized recipe features low cost and high efficiency since it utilizes hydrogen from the hydrated water in natural borax and avoids high temperatures. Our finding is expected to facilitate applications of NaBH4 for hydrogen storage.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
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