JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2012
·Vol. 50
·期 24
·5177-5184
·
IF 3.919
Yonggang Gao,Lin Gu,Yusheng Qin,Xianhong Wang,Fosong Wang
Low-molecular weight oligo(carbonate-ether) diols are important raw materials for polyurethane formation, which with tunable carbonate unit content (CU) may endow new thermal and mechanical performances to polyurethane. Herein, facile synthesis of oligo(carbonate-ether) diols with number average molecular weight ( M n ) below 2000 g mol −1 and CU tunable between 40% and 75% are realized in high activity by immortal copolymerization of CO 2 /propylene oxide (PO) using zinc-cobalt double metal cyanide complex (Zn-Co-DMCC) in the presence of sebacic acid (SA). M n of the oligomer is in good linear relationship to the mole ratio of PO and SA (PO/SA) and hence can be precisely controlled by adjusting PO/SA. Besides, the molecular weight distribution is quite narrow due to the rapid reversible chain transfer in the immortal copolymerization. High pressure and low temperature are favorable for raising CU. In all the reactions, the weight fraction of propylene carbonate ( W PC ) can even be controlled as low as 2.0 wt %, and the catalytic activity of Zn-Co-DMCC is above 1.0 kgg −1 cat. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
研究领域:
高分子化学
·
催化化学
·
绿色化学
·
功能材料
·
聚合物合成
·
二氧化碳利用
✓ 已验证
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2023
·
IF 4.8
Menghua Liu,Shuangying Li,Zhi Li,Yanhui Li,Yue Zhang,Jingwen Niu,Linchun Nie,Chunmao Chen,Qingxiang Zhou
Amoxicillin is one of the most important semi-synthetic penicillin broad-spectrum β-lactam antibiotics and has achieved many applications. There are few reports on its application for synthesizing carbon dots (CDs). Present work explored the possibility of amoxicillin converted into CDs with sodium carbonate used as the co-reactant employing facile hydrothermal method. The obtained CDs exhibited good selectivity and sensitivity to benzidine and could be explored as an effective fluorescence probe for monitoring benzidine. The fluorescence intensity of CDs was quenched based on the principle of static quenching due to the formation of a non-fluorescent complex between CD and benzidine. Within the range of 0.2–2 μM and 2–16 μM, CDs possessed good linear characteristics, high sensitivity, and a low detection limit of 0.08 μM. The results demonstrated that the fluorescence probe possessed the merits of simplicity, rapidity, low cost, short analytical time, high selectivity and sensitivity, and good stability. According to the verification results from the real water samples, the fluorescence probe had high reliability and feasibility, and could be employed for monitoring benzidine in waters.
研究领域:
分析化学
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环境监测
·
纳米材料
·
荧光传感
·
药物化学
✓ 已验证
DOI
高影响因子
IONICS
·
2019
·Vol. 26
·期 1
·263-272
·
IF 2.289
Luo X. Y.,Meng B.,Xia Z. D.,Chen Q. B.,Dong D. Z.,Zhao M. Y.
In order to investigate the effects of Na 2 CO 3 /ZnO co-addition on the sinterability and electrical conductivity of BaZr 0.1 Ce 0.7 Y 0.1 Sc 0.1 O 3-δ (BZCYSc) ceramic, Na 2 CO 3 and ZnO were added and BZCYSc/ZnO/Na 2 CO 3 ceramic was prepared by mechanical ball milling and high-temperature sintering in air. The crystalline structure, micro-morphology, chemical composition, density, and electrical conductivity of the sintered ceramics were characterized by XRD, SEM, EDS, Archimedes method, and electrochemical impedance spectrum, respectively. The grains size of BZCYSc-2%ZnO-5%Na 2 CO 3 is about 2.5~5 μm. Na 2 CO 3 /ZnO co-addition is beneficial to improve the sinterability and electrical conductivity of BZCYSc. The sintering temperature of BZCYSc can be lowered from 1550 to 1350 °C when 2 mol%ZnO is added. At 550 °C, the electrical conductivities of BZCYSc-2%ZnO-10%Na 2 CO 3 and BZCYSc are 1.90 × 10 −3 S/cm and 1.81 × 10 −3 S/cm. The activation energies of BZCYSc and BZCYSc-2%ZnO-10%Na 2 CO 3 are 0.7529 eV and 0.5641 eV, respectively.
研究领域:
材料科学
·
无机非金属材料
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固态离子学
·
能源材料
·
陶瓷工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2015
·Vol. 42
·期 1
·1660-1665
·
IF 2.605
Yanxia Zheng,Gang Dong,Liyong He,Gang Wu,Huade Zheng,Chunlin Deng
Calcium phosphate layers, which are widely applied on the surface of biomaterials, are important for improving tissue regeneration performance. The composition of layers formed on the surface of biomaterials differs depending on the soaking fluid. Herein, revised simulated blood fluid and fast calcification solution were investigated as immersing solutions for the mineralization of hydroxyapatite ceramics. The morphology of the hydroxyapatite particles and precipitate formation on the hydroxyapatite ceramics surface were characterized by transmission electron microscopy . Furthermore, scanning electron microscopy was used to examine the morphology of the bioactive ceramics surface. The structure of the layers was determined by selected-area electron diffraction. The prepared hydroxyapatite powders were characterized by powder X-ray diffraction. The results showed that hydroxyapatite was preferentially formed on the hydroxyapatite ceramics surface in revised simulated blood fluid and octacalcium phosphate precipitated in fast calcification solution. Additionally, the content of HCO 3 - in the mineralization fluid strongly influenced the crystal phase composition and morphology of the calcium phosphate layers on the bio-ceramics materials studied herein.
研究领域:
生物材料学
·
组织工程
·
无机化学
·
生物医学工程
·
牙科材料
·
骨再生
✓ 已验证
DOI
高影响因子
Journal of CO2 Utilization
·
2019
·
IF 5.189
Wei Zhang,Fengzhen Zhang,Liping Ma,Jing Yang,Yi Wei,Deqi Kong
In this work, we propose a novel, effective, energy efficient technology to reduce CO 2 emissions and fully use the calcium in the solid waste by-product phosphogypsum (PG), by capturing CO 2 from the PG decomposition product’s hydrolysis solution. Experiments were conducted to investigate the technical feasibility and the influence of temperature and CO 2 partial pressure on CO 2 capture, as well as CO 2 loading on CO 2 sorption capacity. The results showed that > 90 % of the total calcium ions in the solution were converted into calcium carbonate (CaCO 3 ). Furthermore, a decrease in temperature and an increase in CO 2 partial pressure improved CO 2 uptake, with the latter having a greater effect on CO 2 capture capacity than the former. Moreover, kinetic analysis demonstrated that a higher temperature and CO 2 partial pressure increased the absorption rate; and showed that the CO 2 absorption rate is highly affected by the CO 2 loading levels. The thermodynamic analysis indicated that CO 2 absorption heat significantly declined as a function of increasing CO 2 loading. CaO from the calcination of carbonate was added to the hydrolysis solution and significantly enhanced its CO 2 capture ability. Thus, the hydrolyate of PG decomposition products in combination with CaO reinforcement may be a promising method for CO 2 capture.
研究领域:
环境化学
·
工业生态学
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固废资源化
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碳捕集与封存
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过程强化
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2013
·Vol. 129
·期 6
·3473-3481
·
IF 1.395
Wan-Zhong Lang,Hai-Yan Niu,Ya-Xin Liu,Chun-Xia Liu,Ya-Jun Guo
The waste perfluoro-ion-exchange membranes (PFIEMs) in chlor-alkali industry were regenerated and used to the separation of dimethyl carbonate (DMC)/methanol (MeOH) mixtures by pervaporation process. The energy-dispersive spectrum (EDS) demonstrates that the impurities on the surfaces of waste PFIEMs can be effectively cleared by the regeneration process. The degree of swelling, sorption, and pervaporation properties of the regenerated PFIEMs with different counter ions were investigated. The results indicate that the counter ions of PFIEMs conspicuously influence the degree of swelling, sorption, and pervaporation properties for DMC/MeOH mixtures. The degree of swelling and solubility selectivity both decreases with the alkali metal counter ions in the sequence: Li + > Na + > K + > Cs + . The degree of swelling increases with MeOH concentration increasing in feed liquid. The pervaporation measurements illustrate that the permeation flux decreases and the separation factor increases with the rising in ion radius of counter ions. The increase of feed concentration (MeOH) and feed temperature is advantageous to improve permeation flux while at the cost of separation factor decreasing. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
研究领域:
高分子材料
·
化学工程
·
膜科学与技术
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环境化工
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分离科学
✓ 已验证
DOI
高影响因子
Journal of Nanomaterials
·
2019
·Vol. 2019
·期 1
·5290496
·
IF 2.233
Zhenzhu Yu,Fei Nan,Lu Su,Shaofei Zhang,Yan He
Intercalation and exfoliation are key steps in the preparation of graphene by thermal exfoliation, and they determine the quality of the final product. Therefore, it is important to explore the influence of intercalation agents on the intercalation and exfoliation of graphite. In this article, ammonium bicarbonate is intercalated into graphite with different degrees of oxidation to form a graphite intercalation compound (GIC) by means of ultrasound and stirring. Then, they are exfoliated by being heated at high temperatures. After ammonium bicarbonate intercalation and heating treatment, XRD, TG, and BET show that the intercalation and exfoliation effect of graphite oxide (GO) is better than that of graphite (G) and expanded graphite (EG). The intercalation mechanism is that the ammonia molecule in ammonium bicarbonate solution contains a wedge-shaped structure and active point, which provides empty orbits for graphite electrons and forms edge intercalation through physical interaction at the same time.
研究领域:
材料科学
·
纳米材料
·
物理化学
·
碳材料
·
功能材料
✓ 已验证
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2021
·Vol. 9
·期 4
·105785
·
IF 5.909
Jinjia Guo,Yongmei Wang,Zhao Luo,Feng Zhang,Dewang Yang
Carbon cycle in coastal water is a significant dynamic component of global carbon budget , however, the diverse sources, carbon sinks and their complex interactions remained poorly understood. In order to detect the dissolved inorganic carbon (DIC) and their interactions, gas-liquid Raman spectroscopy was built and applied to simultaneously detect the constituents of air, dissolved CO 2 , HCO 3 - and chlorophyll in coastal water. The linear fitting curve between peak intensity and concentration was built for the quantitative analysis of HCO 3 - and CO 2 , meanwhile, the fluorescence peaks of chlorophyll at 679 nm were detected for the qualitative analysis. For the multi-components analysis, typical Raman spectra of the constituents of air, dissolved CO 2 , HCO 3 - in seawater, and the fluorescence spectra of chlorophyll in seawater were detected. Results showed that the time dependent change of CO 2 and O 2 in the air exhibited a contrary tendency, while that of dissolved CO 2 and O 2 was curved like a cosine. The changing tendency of relative concentrations of dissolved CO 2 was about 2 h earlier than CO 2 in air, due to the life activity of microorganisms driving the gas exchange at the air-sea interface. Furthermore, the study makes a study on the relationship between DIC and chlorophyll based on the detection of HCO 3 - and chlorophyll in coastal water, indicating that this gas-liquid Raman spectroscopy could successfully provide real-time analysis of multicomponent DIC in the air-sea exchanging process.
研究领域:
海洋化学
·
环境光谱学
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碳循环
·
分析化学
·
生物地球化学
✓ 已验证
DOI
高影响因子
CATALYSIS COMMUNICATIONS
·
2011
·Vol. 15
·期 1
·52-55
·
IF 2.827
Ben Qi,Lan-Lan Lou,Kai Yu,Wenyue Bian,Shuangxi Liu
A series of manganese oxides (MnO, Mn 3 O 4 , Mn 2 O 3 and MnO 2 ) were prepared and firstly applied as heterogeneous catalysts for the liquid phase epoxidation of alkenes with 30% H 2 O 2 in bicarbonate solution. Under our experimental conditions, MnO exhibited superior activity for the conversion of styrene to achieve ca. 100% with 92.4% selectivity of epoxide, compared to the other three manganese oxides as well as other metal oxides. Furthermore, recycling studies showed the good recyclability of MnO as a heterogeneous catalyst, which did not lose the catalytic activity after four reuses appreciably.
研究领域:
催化化学
·
有机合成
·
材料化学
·
绿色化学
·
工业化学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE CHINESE CHEMICAL SOCIETY
·
2020
·Vol. 67
·期 9
·1715-1720
·
IF 1.554
Shu-Zhen Yang,Zhi-Qiang Dong,Cheng-Cheng Yin,Hui-Juan Yue,Wei-Wei Gao,Feng-Ke Yang
In this paper, a green process for the synthesis and separation of caffeine was reported. Theophylline sodium is used as the raw material, diazabicyclo[5.4.0]undec-7-ene as the catalyst, and Turkey red oil as the solvent, particularly, dimethyl carbonate was adopted in place of high toxic dimethyl sulfate to form a mixture of caffeine and by-product sodium bicarbonate. After converting sodium bicarbonate to sodium carbonate, the solubility difference between caffeine and sodium carbonate at 40°C was for the first time utilized to achieve the purpose of separating caffeine with an excellent yield of 98.4% and a purity of greater than 99.0%. Furthermore, both the reaction mother liquor and separation mother liquor can be recycled and reused during the reaction and separation processes, respectively, with little caffeine loss. No industrial waste was discharged in the process of the improved synthesis and separation, which is therefore environmental friendly.
研究领域:
有机化学
·
药物化学
·
绿色合成
·
分离科学
·
环境科学
✓ 已验证
DOI
高影响因子
CRYSTAL RESEARCH AND TECHNOLOGY
·
2015
·Vol. 50
·期 4
·312-318
·
IF 0.935
Yadong Hu,Yinghua Zhou,Xurong Xu,Ruikang Tang
The evolution of amorphous calcium carbonate (ACC) into crystals in ethanol/water binary solvents under ambient temperature was investigated, and it was found to depend on the volume ratio of ethanol to water (R). Calcite remained dominant when the amount of water was high (R = 1/3). A slight change in the amount of ethanol (R = 3/1) could lead to a dramatic change in the polymorph from calcite to aragonite. However, when poly (allylamine hydrochloride) (PAH) was added at R = 3/1, almost pure vaterite could be obtained, which has a specific morphological variation (from hollow microspheres to cloud-like). This study provides an alternative polymorphic route for the CaCO 3 mineral by using the evolution of ACC in different solvent environments, which provides some useful clues for understanding the importance of kinetic control of the morphologies and polymorphs of a wide range of inorganic materials. In addition, this simple mild phase-controlled synthetic method could be scaled up as a green chemistry route for the industrial production of different polymorphs of CaCO 3 .
研究领域:
材料化学
·
结晶学
·
纳米材料
·
生物矿化
·
绿色化学
·
功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS CHEMISTRY
·
2011
·Vol. 21
·期 40
·16028-16034
·
IF 5.101
Jun Shi,Zhengzheng Zhang,Gefei Li,Shaokui Cao
Alginate/CaCO3 hybrid beads with pH- and thermal-responsive drug release properties were prepared under compressed CO2 using aliphatic poly(urethane-amine)s (PU) as the thermal-responsive component. Polyacrylic acid (PAA) was used as a crystal growth additive to control the structure of the hybrid beads. The hybrid beads were characterized by using scanning electron microscopy, X-ray powder diffraction and thermogravimetric analysis. The interaction between PAA and aliphatic PU contributed to the formation of alginate beads with a compact CaCO3 shell. Indomethacin release behaviour was found to be pH- and thermal-responsive. The release profiles were sustained with CaCO3 microparticles, indicating that the compact CaCO3 shell could hinder the permeability of the encapsulated drug and reduce the drug release effectively. The results suggest that the hybrid alginate beads can be used as “smart” polysaccharide materials for sustained dual-responsive drug delivery.
研究领域:
生物材料
·
药物递送系统
·
高分子科学
·
纳米医学
·
药剂学
·
生物化学
·
组织工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）