FUEL
·
2018
·
IF 4.908
Zhong-Qiu Liu,Xian-Yong Wei,Fang-Jing Liu,Guang-Hui Liu,Zhi-Min Zong
Trifluoromethanesulfonic acid supported on attapulgite powder (TFMSA/AP) and Mg 2 Si/γ-Al 2 O 3 were facilely prepared by impregnating TFMSA onto AP and Mg 2 Si onto γ-Al 2 O 3 . The extraction residue from Yiwu lignite (YL ER ) was subjected to non-catalytic hydroconversion (NCHC) and catalytic hydroconversion (CHC) over TFMSA/AP and Mg 2 Si/γ-Al 2 O 3 , respectively. Detailed molecular compositions of the soluble portions from the NCHC (SP NCHC ) and CHC over TFMSA/AP (SP CHC-A ) and Mg 2 Si/γ-Al 2 O 3 (SP CHC-B ) were characterized with a gas chromatograph/mass spectrometer. As a result, the yields of SP CHC-A and SP CHC-B are 19.6% and 17.5%, respectively, which are much higher than that of SP NCHC (1.04%), suggesting that both TFMSA/AP and Mg 2 Si/γ-Al 2 O 3 show excellent activity for the CHC of YL ER . Arenes and arenols are predominant in SP CHC-A and SP CHC-B , respectively, while large amounts of alkanoates were detected in SP NCHC . The results indicate that TFMSA/AP effectively catalyzes the cleavage of C ar –C alk and C alk –O bridged bonds (BBs) in YL ER , while Mg 2 Si/γ-Al 2 O 3 significantly promotes the cleavage of C–O BBs in YL ER . Di(1-naphthyl)methane, 1-methylnaphthalene, oxydibenzene, and benzyloxybenzene were used as coal-related model compounds (CRMCs) for the CHC to further explore the catalysis of TFMSA/AP and Mg 2 Si/γ-Al 2 O 3 . The results show that TFMSA/AP not only releases mobile H + but also heterolytically splits H 2 to form an immobile H − and a mobile H + , leading to the cleavage of C alk –C ar and C alk –O BBs in the CRMCs. In contrast, Mg 2 Si/γ-Al 2 O 3 facilitates heterolytically splitting H 2 to an immobile H + and a mobile H − , resulting in the cleavage of C–O BBs in the CRMCs.
研究领域:
化学工程
·
煤炭化学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Healthcare Materials
·
2022
·Vol. 12
·期 3
·2201799
·
IF 11.092
Congying Wei,Weili Shi,Chuangqi Zhao,Shuai Yang,Jiajia Zheng,JinPan Zhong,Tianyi Zhao,Simin Kong,Xi Gong,Mingjie Liu
Injectable hydrogels have recently emerged as alternatives to sutures for various clinical indications. However, existing injectable hydrogels are unsuitable for hemostasis in minimally invasive surgery because of their weak interfacial adhesion and complex/prolonged processing. Herein, a superwetting injectable hydrogel composed of oppositely charged polysaccharides is developed. The spontaneous spreading of the injectable hydrogel on the surfaces achieves complete wetting and forms tight interfacial contact by absorbing the interfacial water. The superwetting ability and subsequent covalent crosslinking perform fast and ultrastrong wet adhesion (140 kPa) on the tissue surface. Ex vivo porcine and in vivo rat models show that the hydrogel successfully leads to the aggregation of erythrocytes for targeted hemostasis (in less than 12 s) without requiring external adjuncts, and no postsurgical adhesions to the peripheral tissues. This further demonstrates that hydrogel can act as an effective hemostasis agent in laparoscopic surgery in a rabbit model. Overall, the strong wet adhesion, antibacterial properties, and easy operability make this injectable hydrogel a promising candidate for hemostasis applications, as it can successfully combine clinical efficacy and transformation opportunities for minimally invasive surgery.
研究领域:
生物医学工程
·
材料科学
·
外科手术
·
止血
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2013
·
IF 3.41
Jin Zhao,Jun Xie,Chak-Tong Au,Shuang-Feng Yin
We report a new strategy for one-pot synthesis of potassium-loaded MgAl oxides using KOH to adjust the pH value of the reaction system. The as-prepared solid superbases were studied by N 2 physisorption method, energy-dispersive X-ray spectroscopy, powder X-ray diffraction, and Fourier transform infrared. The superbasic sites were characterized by the use of Hammett indicators and CO 2 temperature-programmed desorption. We found that with a base strength ( H – ) above 26.5, the potassium-loaded MgAl oxides showed high catalytic activity for Knoevenagel condensation at room temperature. Furthermore, the higher the superbasicity and/or the more the amount of superbasic sites, the better is the catalytic activity. The findings open up a new route for the synthesis of new functional superbases using composite oxides as supports.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2023
·Vol. 24
·期 18
·14313
·
IF 5.6
Jiaqi Shi,Lei Wang,Shang Gao,Jianbo Huang,Hao Yang,Hao Lu,Shaohua Cao
Alkali-activated persulfate (PS) is widely used in situ in chemical oxidation processes; however, studies on the innovation of the alkali activation process are very limited. Two supported solid superbases, namely KNO3/γ-Al2O3(KAl) and KNO3/SBA-15/MgO (KSM), respectively, were prepared and used to activate persulfate to degrade DCF in this work. The results showed that the superbases elevated the solution pH once added and thus could catalyze persulfate to degrade diclofenac efficiently above pH 10.5. The catalytic efficiency of KAl was close to that of sodium hydroxide, and that of KSM was the highest. The mechanism might be that, in addition to raising the solution pH, some potassium existed as K2O2, which had a strong oxidizing effect and was conducive to DCF removal. Hydroxyl, sulfate and superoxide radicals were all found in the reaction system, among which hydroxyl might play the most important role. The material composition ratio, common anion and humic acid all had some influences on the catalytic efficiency. A total of five intermediates were found in the KSM/PS oxidation system, and six oxidation pathways, which were hydroxylation, dehydrogen, dechlorination, dehydration, decarboxylation, and C-N bond breakage, might be involved in the reaction process. Several highly toxic oxidation products that should be paid attention to were also proposed.Keywords:base-activated persulfate;catalytic mechanism;diclofenac;solid superbase
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MACROMOLECULAR RAPID COMMUNICATIONS
·
2023
·
IF 4.6
Zhengxu Jin,Hongyan Liu,Huijuan Zhang
Ionogels possess high conductivity, stretchability, and adhesion, making them promising as flexible sensors. However, it remains challenging to fabricate an ionogel which integrates excellent environment endurance, superior mechanical strength, high self-healing efficiency, and super adhesion. Herein, a supramolecular ionic liquid is synthesized using calcium chloride and 1-butyl-3-methylimidazolium chloride. An advanced ionogel based on this supramolecular ionic liquid is conveniently constructed by a one-pot method with acrylamide and acrylic acid as monomers. The supramolecular cross-linking network, formed by affluent coordination interactions, hydrogen bonds, and electrostatic interactions, provides the ionogel with ideal mechanical strength (tensile strength up to 1.7 MPa), high self-healing efficiency (up to 149%), super adhesion (up to 358 kPa on aluminum), excellent solvent tolerance (less than 10% weight increase, high mechanical and sensing performance retention after being soaked in organic solvents), and low-temperature endurance (breaking elongation can reach 87% at −30 °C). The supramolecular ionogels can function as multi-mode sensors, capable of monitoring strain and different amplitudes of human movements in real-time. Moreover, the sensing performance of ionogels remains unaffected even after being self-healed or exposure to organic solvents. It is expected that this study could offer valuable design ideas to construct advanced gel materials applicable in complicated environment.
研究领域:
材料科学
·
传感器技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Green Processing and Synthesis
·
2021
·Vol. 10
·期 1
·874-881
·
IF 2.83
Xin Zhou,Ge Gao,Guangxiang He,Xiaoyan Guo,Haibo Jin,Lei Ma
The side-chain alkylation of cumene and ethylene over a solid superbase catalyst K/KOH/ γ -Al 2 O 3 is investigated. The effects of the reaction temperature, pressure, and time on the conversion of cumene and selectivity of tert -amylbenzene (TAB) are discussed. The experimental results show that the conversion of cumene to tert -pentylbenzene increases with the increase in reaction temperature and ethylene pressure. The catalytic reaction has certain operational flexibility in terms of the reaction temperature, pressure, and time. In addition, the catalytic reaction can achieve directional conversion. The optimum operating conditions are obtained using a single factor test. The conversion of cumene is 99.8% and the selectivity toward TAB is 97.9% under catalyst concentration of 4 wt%, reaction temperature of 55°C, reaction pressure of 0.45 MPa, and reaction time of 30 min. The deactivation of catalyst is mainly caused by oxygen and water in the raw material.
研究领域:
催化化学
·
有机合成
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 137
·期 37
·49118
·
IF 2.52
Chunhui Luo,Ning Wei,Xinxin Sun,Faliang Luo
Developing hydrogels with excellent mechanical performances and multiple functions is challenging. Herein, polyvinyl alcohol (PVA) and grape seed extracted polymer (GSP) were used to achieve this goal. The hydrogel was firstly cross-linked by crystalline regions of PVA upon freezing–thawing cycles, it was further immersed in ammonium sulfate (AS) solution to induce the hydrophilic to hydrophobic transition of GSP. The relationship between microstructures and mechanical properties of the obtained PVA–GSP hydrogel was revealed. The results showed that the PVA–GSP precursor hydrogels were weak due to the uneven network and lower cross-link density. After soaking in ammonium sulfate solution, the network became more dense and uniform because of the hydrophilic to hydrophobic transition of GSP. Meanwhile, frictions between polymer chains increased. As a result, ultra-strong (tensile stress = 20.5 MPa), antifatigue (>95%), self-healable (healed stress = 10.0 MPa), and conductive hydrogels were obtained. The strength and toughness of our gel are among top values in literature to date. Furthermore, the swollen gel even after soaking in DI water for 36 hr still maintained tensile strength at the megapascal level, superior to most water-rich hydrogels. This tough and functional gel might find potential applications in cartilage repair, artificial skin, and sensors.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULES
·
2025
·
IF 5.2
Shuxing Yin,Yi Ding,Ying Zhang,Can Zhou,Cheng Qian,Guojun Che,Chuangqi Zhao,Lei Jiang
For the applications of synthetic hydrogels in wearable devices and underwater protection fields, both exceptional mechanical properties and high transparency are highly desired. Here, we produce a superstrong and transparent hydrogel with a homogeneous and densely interconnected polymer network. The obtained hydrogel has exceptional mechanical properties, for example, an ultimate strength of 44.2 ± 1.0 MPa and a toughness of 153.0 ± 3.6 MJ m–3. The homogeneous triple-network structure endows the hydrogel with a high transparency of 90% and an excellent tensile strength of 35.5 ± 0.8 MPa in an underwater environment. The multiple effective energy dissipation mechanisms, including ion cross-linking, crystalline domains, and entanglements, synergistically enhance the mechanical properties. Moreover, such a superstrong and transparent hydrogel can be coated on the surface of underwater optical devices, playing the role of antifogging, antioiling, and wear resistance. Our strategy provides a new avenue to design functional hydrogel materials with excellent mechanical properties and high transparency.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Yichen Wan,Shuaishuai Huang,Yuxuan Sun,He Zhu,Qingbin Zheng,Qi Zhang,Shiping Zhu
Developing superstrong adhesives that can be detached via an environmental friendly trigger under mild operation conditions is highly desirable in industry and it can significantly contribute to sustainability. This work provides a novel design of particular eutectogel adhesives based on poly(acrylic acid)-deep eutectic solvent (PAA-DES). The synthesized adhesives can bond strongly with versatile substrates and be readily detached via simple water soaking. The eutectogel adhesive establishes strong adhesion interactions with the surface of adherends through abundant hydrogen bonds and ion-substrate interactions, with an ultrastrong adhesion strength reaching as high as 12.50 MPa on the glass substrate. The adherends could be easily released by water soaking for several minutes with no damage to the system. Such a novel approach for developing detachable adhesives is believed to have high potential in commercialization that requires temporal joining and assembly processes, including optical lens drilling and wafer dicing.
研究领域:
材料科学
·
可持续性技术
✓ 已验证
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2017
·
IF 3.752
Xiang-Xue Liu,Zhi-Min Zong,Wei-Tu Li,Xiang Li,Zhan-Ku Li,Sheng-Kang Wang,Xian-Yong Wei
A novel and highly active magnetic solid superbase (MSSB) with extraordinary recovery and recycling properties was prepared by impregnating Mg 2 Si onto mesoporous silica coated magnetite via one-pot preparation and successfully applied in the catalytic hydroconversion (CHC) of sawdust at 220 °C. Detailed molecular compositions of the soluble portions from non-catalytic hydroconversion (SP NCHC ) and CHC (SP CHC ) were characterized with a Fourier transform infrared spectrometer and gas chromatograph/mass spectrometer (GC/MS). As a result, the yield of SP CHC is significantly higher than that of SP NCHC and most of the GC/MS-detectable compounds in SP CHC are guaiacols , while SP NCHC is rich in guaiacols and esters, indicating that MSSB effectively catalyzed the cleavage of C O bridged bonds in sawdust. The mechanism for catalytically hydrocracking C O bridged bonds over MSSB is proposed using benzyloxybenzene and oxybis(methylene)dibenzene as model compounds. MSSB can be easily separated by using an external magnetic field and the recovered MSSB proved to be still highly active for catalyzing the hydrocracking of C O bridged bonds in sawdust.
研究领域:
化学工程
·
生物质转化
✓ 已验证
产品关联
DOI
高影响因子
TEXTILE RESEARCH JOURNAL
·
2024
·
IF 1.6
Chaoxu Han,Yan Guo,Ruirui Yang,Shuyue You,Mina Han
Composite medical dressings are made by combining different materials to achieve functions that cannot be realized by a single material, making it an important research direction for medical dressings. This study utilized the unique grooved structure of lotus stem fibers, and the functionality provided by different preparation processes for each layer of material to prepare a medical dressing that can achieve super-strong liquid absorption and storage effects. The prepared materials were characterized and analyzed through liquid absorption performance tests, Fourier transform infrared spectroscopy and scanning electron microscopy. The results showed that the pore structure of modified chitosan hydrogel, the curled distribution of lotus stem fibers in the material, and the moisture-wicking structure contribute to improving the liquid absorption properties. The composite dressing prepared using the optimal process for each layer of material exhibited moisture absorption and retention rates of 591.34% and 87.99%, respectively, demonstrating excellent liquid absorption properties. The antibacterial properties of the composite dressing were also tested against two common bacteria, and the dressing showed good antibacterial performance. The results indicated that the self-assembled composite medical dressing made from lotus stem fibers meets the preparation requirements, and has good application prospects for use in medical dressings.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
CATALYSIS COMMUNICATIONS
·
2011
·
IF 2.827
Yudan Wei,Shuguo Zhang,Shuangfeng Yin,Chang Zhao,Shenglian Luo,Chak-tong Au
We report for the first time the synthesis of a novel solid superbase that was derived from lanthanum–magnesium composite oxide and KOH through thermal treatment. The as-prepared material shows base strength ( H – ) above 26.5 and is a high-efficiency catalyst for solvent-free Knoevenagel condensation at room temperature. The results of the present study open up a new dimension for the use of composite oxides as new support materials in the synthesis of superbases.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）