JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2009
·
IF 2.063
Dongwei Wei,Lishuo Wang,Chao Zhang
Solid−liquid equilibria have been measured for binary mixtures of 1,8-cineole with p-cymene, β-pinene, and camphene, respectively, using differential scanning calorimetry (DSC) over the whole composition concentration range. All three are simple eutectic systems. The eutectic point of the (1,8-cineole (1) + p-cymene (2)) mixture is at 200.0 K and x1 = 0.124, the (1,8-cineole (1) + β-pinene (2)) mixture at 205.6 K and x1 = 0.154, and the (1,8-cineole (1) + camphene (2)) mixture at 251.8 K and x1 = 0.582. An empirical equation of Ott and Goates was used for correlating the experimental data.
研究领域:
物理化学
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2024
·
IF 3.9
Tao Lv,Kexin Wei,Ting Wang,Xiao Wang,Zuguang Liu
A carbon-based acid was prepared by the sulfonation of activated carbon derived from eucalyptus wood waste, a solid waste from wood processing, and characterized by SEM, BET, FT-IR, Raman, XRD and XPS. Due to activation by phosphoric acid and subsequent sulfonation, the resultant carbon-based solid acid can obtain a porous structure, medium surface area and abundant functional groups including sulfonic groups, carboxyl, hydroxyl and other oxygen-containing groups, which provides excellent mass transfer channels and sufficient reactive sites for catalytic reactions. So, the carbon-based solid acid showed excellent catalytic performance for converting α -pinene to camphene with a conversion of up to 99.8 % and a selectivity of 51.2 %, respectively. Quantum chemical theoretical calculations (electrostatic potential, Gibbs free enthalpy of intermediates, molecular size) are used to further analyze the catalytic mechanism of carbon-based solid acids. Theoretical analysis of the carbon positive ions and their energies as well as experimental results under electron-donating co-catalysts suggests that oxygen-containing functional groups on carbon-based solid acids play an important role in improving α- pinene adsorption onto catalyst as well as camphene selectivity. This work provides a promising approach for converting α -pinene to camphene catalyzed by carbon-based solid catalyst.
研究领域:
化学工程
·
催化科学
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产品关联
DOI
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 18
·10606-10611
·
IF 3.119
Geng Huang,Shuolin Zhou,Jian Liu,Shengpei Su,Dulin Yin
Titanate nanotubes, prepared by the hydrothermal reconstitution and modification with hydrochloric acid, were tested as solid acid catalysts in the isomerization of α-pinene under solvent free conditions. The results showed that titanate nanotubes have better catalytic properties than titanium dioxide nanoparticles, and the camphene was the main product for α-pinene isomerization. The effects of several reaction variables, such as reaction temperature, catalyst dosage, and reaction time, on the conversion of α-pinene and the selectivity to camphene were examined. The highest conversion was up to 97.8% with selectivity to camphene of 78.5% under the mild reaction conditions, and the catalyst also showed outstanding reusability after four runs. It is proposed that appropriate surface acidic sites and opened nanotubular structures are mainly responsible for the excellent catalytic performance of titanate nanotubes materials.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Jinzhu Zou,Huiwen Xiong,Yujuan Huang,Zhiguo Wang,Jianhui Wen,Wen Du,Jun Cao
In order to control the pore characteristics and macroscopical performance of porous ceramics , roles of the freeze casting parameters are the key points. Herein, aligned dendritic porous SiC was fabricated by freeze casting of PCS-camphene solutions with different solid loading, freeze front velocity, temperature gradient , and freezing temperature. Influence of these parameters on the microstructure and compressive strength of porous SiC was investigated. With increasing the PCS content, freeze temperature, freeze front velocity or temperature gradient, degree of undercooling of the camphene was increased, resulting in the formation of smaller pore size, decreased porosity and increased compressive strength . Compared to variables of freeze temperature and temperature gradient, increased freeze front velocity was more efficiency in improving the compressive strength of porous SiC, owing to the formation of smaller pore size and longer secondary dendritic crystals. Promising micron-sized porous SiC with high porosity (79.93 vol%) and satisfactory strength (15.84 MPa) was achieved for 10% PCS-camphene solution under optimized freezing conditions.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
DOI
高影响因子
Membranes
·
2022
·Vol. 12
·期 9
·867
·
IF 4.562
Zhen Wang,Xiaojuan Wang,Zhantong Sun,Xiaofeng Wang,Hongdong Wang,Congjie Gao,Xueli Gao
Inorganic membranes have been developed rapidly in recent years because of excellent anti-fouling performance, high mechanical strength and outstanding resistances to acid and alkali. However, the high production cost still restricts its large-scale industrial application. In this work, an environmental friendly unidirectional freezing method via introducing camphene as a reusable template was adapted to prepare porous cement membranes (PCMs). The naturally formed and highly aligned porous structures of PCMs could be divided into three parts: a dense layer, a transition layer and a supporting layer. With the solid content rising from 40 wt.% to 60 wt.%, the pore size of the PCMs decreased from 3.34 nm to 3.62 nm, the bovine serum albumin (BSA) rejection increased from 81.3% to 93.5% and water flux decreased from 346.8 L·m−2·h−1to 167.3 L·m−2·h−1(0.2 MPa). Significantly, the performance of PCMs was maintained; even the camphene was reused 20 times. Additionally, the recovery rate of camphene could be reached up to 97.16%. Therefore, this method is cost effective and environmental friendly, which endowed the PCMs great potential in water treatment.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2025
·
IF 2.5
Lu-yang Han,Dong Yang,Hong-Liang Wang,Zhe Gao,Yin-Yu Qi,Yang Xu,Tao Zhou,Jianjun Chu
A new type of antibacterial bone cement that relies on surface stereochemistry and is added with antibacterial monomer isobornyl acrylate (BA) is reported. In this study, BA was integrated into poly(methyl methacrylate) (PMMA) bone cement through liquid-phase modification to create a non-leaching antibacterial bone cement (NLBC). The maximum temperature, setting time, antibacterial activity, mechanical strength, and biocompatibility of this NLBC were comprehensively evaluated. The results showed that the BA cement exhibited exceptional antibacterial and mechanical properties. The 30wt% BA cement demonstrated an antibacterial activity of 81.0 ± 3.1% against Staphylococcus aureus and a compressive strength of 72.10 ± 1.97 MPa. The BA cement exhibited good biocompatibility both in vitro and in vivo. Furthermore, we compared the antibacterial activity, mechanical properties, and biocompatibility of the BA cement with three previously reported bone cements, which contain the antibacterial monomers 2-(tert-butylamino)ethyl methacrylate (TBAEMA), methacrylate derived from benzothiazole (BTTMA), nitrofuran methacrylate (NFMA), respectively. The findings of this study have important implications for the advancement of antibacterial bone cement and its application in medical implants.
研究领域:
医学材料学
·
生物医学工程
✓ 已验证
DOI
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 4
·1875
·
IF 4.6
Zhong-Lei Meng,Rong-Xiu Qin,Ru-Si Wen,Gui-Qing Li,Zhong-Yun Liang,Jun-Kang Xie,Yong-Hong Zhou,Zhang-Qi Yang
This study examined the preparation of isobornyl acetate/isoborneol from camphene using an α-hydroxyl carboxylic acid (HCA) composite catalyst. Through the study of the influencing factors, it was found that HCA and boric acid exhibited significant synergistic catalysis. Under optimal conditions, when tartaric acid–boric acid was used as the catalyst, the conversion of camphene and the gas chromatography (GC) content and selectivity of isobornyl acetate were 92.9%, 88.5%, and 95.3%, respectively. With the increase in the ratio of water to acetic acid, the GC content and selectivity of isobornol in the product increased, but the conversion of camphene decreased. The yield of isobornol was increased by adding ethyl acetate or titanium sulfate/zirconium sulfate to form a ternary composite catalyst. When a ternary complex of titanium sulfate, tartaric acid, and boric acid was used as the catalyst, the GC content of isobornol in the product reached 55.6%. Under solvent-free conditions, mandelic acid–boric acid could catalyze the hydration reaction of camphene, the GC content of isoborneol in the product reached 26.1%, and the selectivity of isoborneol was 55.9%. The HCA–boric acid composite catalyst can use aqueous acetic acid as a raw material, which is also beneficial for the reuse of the catalyst.Keywords:α-hydroxyl carboxylic acid;camphene esterification reaction;camphene hydration reaction;green synthesis
研究领域:
化学
·
催化
·
有机合成
·
绿色化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2016
·
IF 1.78
Ruijing Li,Kexin Chen,Geng Li,Guoxiang Han,Sheng Yu,Juming Yao,Yurong Cai
Porous microspheres fabricated from bioceramics have great potential for cell delivery in injectable tissue engineering application. The size and structure of pores in the microspheres are important for the effective protection and transportation of cells. In this study, porous hydroxyapatite microspheres are fabricated through the water-in-oil emulsion method followed by a calcination treatment at the high temperature. Both self-made resorcinol-formaldehyde (RF) composite spheres and camphene are used as pore-forming agents to produce big pores corresponding to the size of RF spheres and connected channel among big pores in hydroxyapatite matrix. The properties of the microspheres are characterized using X-ray diffraction, thermogravimetry analysis, universal material machine, field emission scanning electron microscopy . Cell assays are carried out to evaluate the cellular compatibility of the microspheres. The results showed that the hydroxyapatite microspheres with controllable pore structure and high porosity could be fabricated by this method, which have better strength to resist the compressive force. The microspheres are conducive to support adhesion, proliferation and differentiation of MC3T3-E1 cells. The results indicate that the obtained porous hydroxyapatite microspheres can be a permeable microenvironment for cell delivery in injectable tissue engineering.
研究领域:
生物材料
·
组织工程
·
生物陶瓷
·
细胞生物学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2024
·
IF 5.8
Yuanyuan Liu,Zhilin Tian,Liya Zheng,Bin Li
Porous silica ceramics were prepared by a freeze-casting method using dual solvents as a template, and their microstructure can be regulated by different ratios of solvents. As the camphene content increases, the pore shape gradually changes from prismatic pores to spherical pores, and the pore size first decreases and then increases. A porous silica ceramic showed 76 % porosity and a uniform pore size of 6 µm. It presents excellent thermal insulation properties (thermal conductivity ∼0.17 W m −1 K −1 ), good compressive strength , and a stable dielectric constant (∼1.48). The results of this work shed light on the promising aerospace application of porous ceramics prepared by freeze-casting using dual solvents as a template.
研究领域:
材料科学
·
陶瓷
·
航空航天工程
✓ 已验证
产品关联
DOI
高影响因子
ACTA PHARMACOLOGICA SINICA
·
2024
·
IF 6.9
He Rong-rong,Ma Chuan-rui,He Xin,Dong Yan-xi,Li Hui,Chu Zi-xuan,Yang Xi-he,Wang Jia-qi,Wang Ting,Wang Feng-qing,Du Fei-fei,Rao Ying,Yu Wen-xuan,Gao Xiu-mei,Fan Guan-wei,Cheng Chen,Li Chuan
Translational pharmacological research on traditional medicines lays the foundation for precisely understanding how the medicines function in the body to deliver therapeutic benefits. Borneolum syntheticum (Bingpian) is commonly used in Chinese herbal medicines for coronary heart disease, but its specific cardiovascular impact remains poorly understood. Isoborneol, a constituent of Bingpian, has been found to reduce lipid accumulation in macrophages in vitro, but its oral bioavailability is limited. This investigation aimed to evaluate anti-atherosclerotic effects of Bingpian, based on understanding its first-pass metabolism. Human subjects orally received an herbal medicine containing Bingpian and their plasma samples were analyzed to identify the major circulating compounds of Bingpian, with the metabolism that was also characterized in vitro and in mice. The identified compounds were evaluated for their ability to inhibit macrophage foam-cell formation induced by oxidized low-density lipoprotein. Furthermore, the anti-atherosclerotic effect of repeatedly dosed Bingpian was assessed in ApoE −/− mice fed a high-fat diet. In human subjects, the major circulating compounds of Bingpian were metabolites, rather than their precursor constituents borneol and isoborneol. These constituents were efficiently absorbed in the intestinal tract but underwent significant first-pass metabolism, involving UGT2B7-mediated glucuronidation into borneol-2- O -glucuronide and isoborneol-2- O -glucuronide, respectively, and CYP2A6/2B6/3A-mediated oxidation both into camphor. Despite their poor membrane permeability, hepatic efflux of borneol-2- O -glucuronide and isoborneol-2- O -glucuronide into the systemic circulation was enhanced by MRP3/4. The circulating metabolites, particularly their combinations, markedly inhibited macrophage foam-cell formation induced by oxidized low-density lipoprotein in vitro. Sub-chronic administration of Bingpian (30 mg·kg −1 ·d − 1 , i.g.) for 12 weeks significantly decreased atherosclerotic lesion size and enhanced plaque stability in ApoE −/− mice. Systemic exposure to Bingpian metabolites in mice closely resembles that in humans, suggesting that the pharmacodynamic effects of Bingpian in mice are likely applicable to humans. Overall, the cardiovascular benefits of Bingpian involve reducing atherosclerosis by inhibiting foam-cell formation through its metabolites. This investigation supports that oral Bingpian could be a druggable agent for reducing atherosclerosis.
研究领域:
药理学
·
心血管疾病
·
传统中药
·
代谢
·
转化研究
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of the Mechanical Behavior of Biomedical Materials
·
2023
·
IF 3.9
Ting Tian,Qing Hu,Miao Shi,Cong Liu,Gang Wang,Xiaofeng Chen
Hierarchical pores are important structural components of the bone tissue and are closely related to angiogenesis, nutrient transport, and metabolism involved in the repair of a bone defect. Here, we fabricated a composite scaffold having a hierarchical structure, based on micro-nano bioactive glass (MNBG) incorporated into poly (lactic-co-glycolic acid) (PLGA), and with camphene as a pore-forming agent for bone repair. The results showed that camphene formed abundant micropores in the walls of large pores, resulting in hierarchical pore structures ranging from a few microns to a hundred microns. Moreover, there was 2–3 folds increased in compressive modulus and the scaffolds showed a stable degradation rate and a higher degree of apatite crystallization than ordinary porous scaffolds . The results of in vitro studies showed that, when compared to ordinary porous scaffolds, PLGA-MNBG scaffolds with multi-holes could better promote the proliferation of bone marrow mesenchymal stem cells (BMSCs) and the expression of angiogenic marker (CD31) of human umbilical vein endothelial cells (HUVECs).
研究领域:
生物材料
·
组织工程
·
生物医学工程
·
细胞生物学
✓ 已验证
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Yujiao Cheng,Leng Han,Linhua Huang,Xiang Tan,Houjiu Wu,Guijie Li
Thermal pasteurization decreases the sensory quality of mandarin juice. Flavor composition was determined in four fresh-squeezed and heat-processed mandarin juice varieties using molecular sensory science approaches. The relationships between odorants and sensory profiles were analyzed, and markers for flavor deterioration were screened by multivariate statistical analysis. Seventy-four volatiles were identified, among which 36 odorants with flavor dilution factors ranging from 2 to 128 were detected by multidimensional gas chromatography-mass spectrometry/olfactometry (MDGC-MS/O) coupled with aroma extract dilution analysis (AEDA). Higher intensities of cooked and off-flavor notes were observed in the heated mandarin juice, which was related to the concentration changes of the methional, methanethiol, dimethyl sulfide, and carbon disulfide by partial least squares (PLS) analysis. Ten potential markers (methional, methanethiol, dimethyl sulfide, hydrogen sulfide, β -damascenone, camphene, trans - β -ionone, decanal, d -limonene, and α -pinene) were responsible for the sensory discrimination of fresh-squeezed and heated mandarin juices.
研究领域:
食品科学
·
分析化学
·
感官科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）