HYDROMETALLURGY
·
2014
·
IF 2.224
Mohannad Mayyas,Mohammad Al-Harahsheh,Xian-Yong Wei
Jordanian phosphate ore contains 70–150 parts per million (ppm) uranium. The uranium in the ore tends to dissolve during the leaching of phosphate ore with sulfuric acid to produce phosphoric acid (PA). Solvent extraction (SX) using various extracting agents is widely used to extract uranium from PA. Meanwhile, much research work has been carried out to develop suitable solid phase extractants in order to reduce cost and enhance efficiency. In this study, a new solid phase extractant has been synthesized by anchoring 2-hydroxy-4-aminotriazine onto activated carbon (ACH). The extraction of uranium from Jordanian PA using ACH and the synergistic mixture of di-ethylhexyl phosphoric acid and trioctyl phosphine oxide (DEPA–TOPO) diluted in kerosene were investigated and the performance of each extractant was evaluated and compared. The results showed that 91% extraction and 559.9 ppm loading capacity were achieved after 2 to 3 min mixing time using 0.5 M DEPA–0.125 M TOPO at 20 °C, 410 mV and 1/1 phase ratio. The activation energy ( E a ) of the solvent extraction (− 26.03 kJ mol − 1 ), calculated from Arrhenius plot, indicates that the reaction is barrier-less and exothermic in nature. On the other hand, uranium sorption onto ACH reaches equilibrium after 10 min and about 92% extraction can be achieved at 20 °C, C o = 70 mg/l, V = 200 ml, W = 100 mg and 410 mV; the rate constant for the uranium sorption onto ACH (16.54 × 10 − 3 g mg − 1 min − 1 ) was calculated from the pseudo-second order equation. The countercurrent extraction results showed that ACH has high physical, chemical stability and loading capacity about 618 mg g − 1 . Thermodynamic parameters ( ΔH ads ° = 20.61 kJ mol − 1 , ΔS ads ° = 160.47 J mol − 1 K − 1 , ΔG ads ° (333.3 K) = − 32.87 kJ mol − 1 ) suggest that the adsorption is endothermic and spontaneous in nature, which confirm the feasibility of the process.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2015
·Vol. 54
·期 8
·1036-1043
·
IF 3.113
Xueteng Cao,Daniel Horák,Zesheng An,Zdeněk Plichta
Nonspecific interaction is a key parameter affecting the efficiency of proteins, nucleic acids or cell separation. Currently, many approaches to introduce antifouling properties to materials have been developed. Among these, surface modification with polymer brushes plays a prominent role. The aim of this study was to synthesize new magnetic microspheres grafted with poly( N,N -dimethylacrylamide) (PDMA) that resist nonspecific protein adsorption. Monodisperse macroporous poly(2-hydroxyethyl methacrylate) (PHEMA) microspheres, 4 μm in size, were synthesized by a multiple swelling polymerization method. To render the microspheres magnetic, iron oxide was precipitated inside the microsphere pores. Functional carboxyl groups, introduced by the hydrolysis of the 2-(methacryloyl)oxyethyl acetate (HEMA-Ac) comonomer, were used to react with propargylamine, followed by coupling of a chain transfer agent via an azide-alkyne click reaction. PDMA was grafted from the PHEMA microspheres using reversible addition-fragmentation chain transfer polymerization (RAFT), resulting in surfaces with more than 81 wt % PDMA attached. The successful modification of the microspheres was confirmed by XPS. The magnetic microspheres grafted with PDMA showed excellent antifouling properties as tested in bovine serum protein solutions. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54 , 1036–1043
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NUCLEAR MATERIALS
·
2015
·
IF 1.865
Kuibao Zhang,Guanjun Wen,Dan Yin,Haibin Zhang
Synroc is recognized as the second generation waste form for the immobilization of high-level radioactive waste (HLW). Zirconolite-rich (CaZrTi 2 O 7 ) Synroc minerals were attempted by self-propagating high-temperature synthesis (SHS) using Fe 2 O 3 , CrO 3 , Ca(NO 3 ) 2 as the oxidants and Ti as the reductant . All designed reactions were ignited and sustained using Ca(NO 3 ) 2 as the oxidant, and zirconolite-rich ceramic matrices were successfully prepared with pyrochlore (Ca 2 Ti 2 O 6 ), perovskite (CaTiO 3 ) and rutile (TiO 2 ) as the minor phases. The sample CN-4, which was designed using Ca(NO 3 ) 2 as the oxidant with TiO 2 /Ti ratio of 7:9, was readily solidified with density of 4.62 g/cm 3 and Vickers hardness of 1052 HV. CeO 2 was successfully stabilized by the CN-4 sample with resultant phase constituent of 2M-CaZrTi 2 O 7 and CaTiO 3 .
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 49
·25933-25939
·
IF 3.708
Qingfeng Liu,Yansen Zhang,Zhiguo Zhang,Tongxin Liu,Lei Shi,Guisheng Zhang
This paper describes a highly efficient and facile transformation of substituted oxazolidin-2-ones to methylene-bridged 3,3′-bis(oxazolidin-2-one) derivatives in a mixture solvent of CH2Cl2 (DCM) and N,N-dimethylformamide (DMF) in the presence of NaH at ambient temperature. Isotopic labeling experiments indicated that the C of the bridged methylene group was derived from CH2Cl2 instead of DMF and other unknown substances in the NaH reagent (60% dispersion in mineral oil).
✓ 已验证
产品关联
DOI
高影响因子
POLYMER COMPOSITES
·
2014
·Vol. 36
·期 9
·1597-1605
·
IF 1.455
Ruxangul Jamal,Ahmat Ali,Li Zhang,Yakupjan Osman,Adalet Rahman,Tursun Abdiryim
Poly(3′,4′-ethylenedioxy-2,2′:5′,2″-terthiophene)/ZnO(poly(TET)/ZnO) composites with the ratio of poly(TET) and nano-ZnO from 3:1 to 1:3 were synthesized by hand grinding and ball milling methods, respectively. The photocatalytic activities of the composites were examined through the degradation processes of methylene blue (MB) solution under UV light irradiation, and the possible mechanism for the photocatalytic activity enhancement by synergetic effects between nano-ZnO and poly(TET) was proposed. The results showed that the strong interactions between the poly(TET) and nano-ZnO occurred in the case of ball milling method. The results also proved that the crystallinity of ZnO was not disturbed in both of methods, and the nano-ZnO was uniformly distributed in polymer matrix in the case of ball milling method. The comparative studies showed that the addition of the nano-ZnO could enhance the photocatalytic activities of the composites. The highest degradation efficiency (100%) at 3 h under UV light irradiation occurred in the case of poly(TET)/ZnO(1:1) synthesized by ball milling method. Furthermore, the nanocompsosite displayed higher photocatalytic activity than nano-ZnO, which was due to the holes ( h + ) transferring from the valence band of ZnO to the polymer backbone and the adsorption of MB molecules in polymer matrix via π–π conjugation between MB and aromatic regions of the poly(TET). POLYM. COMPOS., 36:1597–1605, 2015. © 2014 Society of Plastics Engineers
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF STRUCTURAL CHEMISTRY
·
2015
·Vol. 56
·期 3
·458-462
·
IF 0.508
Huang Q. -W.,Liu S. -G.,Li G. -B.,Wang S. -X.,Su W. -Y.,Liang D. -M.,Mao S. -Q.
A new complex Cu(bpbp)Cl 2 ·DMF·H 2 O is synthesized by treatment of CuCl 2 with 2,6-bis(1-phenylbenzimidazol-2-yl)pyidine in DMF. Its structure is characterized by elemental, IR, UV, and single crystal X-ray structure analyses. For the complex: crystal system, triclinic, space group \(P\bar 1\) , a = 1.0537(1) nm, b = 1.1735(1) nm, c = 1.3749(2) nm, α = 112.275(2)°, β = 91.531(2)°, γ = 97.700(2)°, V = 1.553(4) nm 3 , Z = 2. In a distorted trigonal bipyramidal geometry the Cu(II) ion is coordinated by three nitrogen atoms from 2,6-bis(1-phenylbenzimidazol-2-yl)pyridine and two chloride ions. The antiproliferative activities of the complex are screened by MTT assay against HepG2, Huh7, Eca109, and Eca9706 cancer cells. The complex exhibits specific inhibition on Eca9706 cancer cells with the IC 50 value of 28 μM after 48 h treatment. CCDC: 968927.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2015
·
IF 4.321
Fa-tang Li,Biao Wu,Rui-hong Liu,Xiao-jing Wang,Lan-ju Chen,Di-shun Zhao
Inexpensive N-methyl-pyrrolidone (NMP)-based ionic liquids (ILs) are synthesized by coordinating N-methyl-pyrrolidone with anhydrous FeCl 3 or ZnCl 2 . The introduction of metal chlorides lowers the solubility of NMP for actual diesel. The obtained C 5 H 9 NO·0.3FeCl 3 IL shows remarkable extraction ability for dibenzothiophene (DBT) with Nernst partition coefficients ( k N ) above 7.5, which can be attributed to its low viscosity and bifunctional extractive groups of five-membered ring of NMP and unoccupied orbitals of Fe ion. The oxidative desulfurization of DBT using H 2 O 2 as oxidant and ILs as extractants are investigated. The scavenger experiments and electron paramagnetic resonance (EPR) measurement verify the active species is hydroxyl radical ( OH) responsible for the oxidation of DBT. FeCl 3 -based ILs show much better effects in catalyzing H 2 O 2 to generate OH than ZnCl 2 -based ILs. The process and mechanism for extraction and catalytic oxidation of DBT in an oil–ionic liquid–H 2 O 2 system are proposed. The C 5 H 9 NO·0.3FeCl 3 IL shows excellent recycling performance. After six-run experiment, there is only little loss in activity, which can be ascribed to the high solubility (18,190 ppm) of dibenzothiophene-sulfone (DBTO 2 ), the main oxidation product of DBT, in the IL.
✓ 已验证
产品关联
DOI
高影响因子
TALANTA
·
2024
·
IF 5.6
Qiang Tang,Xiaoling Huang,Guangxing Liu,Hongran Huang,Jiayi Zhang,Jihua Wei,Yuanxun Gong,Qianli Tang,Kai Zhang,Xianjiu Liao
This study introduces a novel electrochemical biosensor for detecting Matrix Metalloproteinase-2 (MMP-2), a key biomarker in cancer diagnostics and tissue remodeling. The biosensor is based on a dual-amplification strategy utilizing T7 RNA polymerase isothermal amplification and CRISPR-Cas12a technology. The principle involves the release of a DNA template in the presence of MMP-2, leading to RNA synthesis by T7 RNA polymerase. This RNA activates CRISPR-Cas12a, which cleaves a DNA probe on the electrode surface, resulting in a measurable electrochemical signal.The biosensor demonstrated exceptional sensitivity, with a detection limit of 2.62 fM for MMP-2. This high sensitivity was achieved through the combination of transcriptional amplification and the collateral cleavage activity of CRISPR-Cas12a, which amplifies the signal. The sensor was able to detect MMP-2 across a wide dynamic range from 2 fM to 1 nM, showing a strong linear correlation between MMP-2 concentration and the electrochemical signal. In practical applications, the biosensor accurately detected elevated levels of MMP-2 in cell culture supernatants from HepG2 liver cancer cells, distinguishing them from normal LO2 liver cells. The use of an MMP-2 inhibitor confirmed the specificity of the detection. These results underscore the biosensor's potential for clinical diagnostics, particularly in early cancer detection and monitoring of tissue remodeling activities. The biosensor's design allows for rapid, point-of-care testing without the need for complex laboratory equipment, making it a promising tool for personalized healthcare and diagnostic applications.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2024
·Vol. 25
·期 2
·1153
·
IF 4.9
Hongxue Gao,Zhiqiang Liu,Fengrui Song,Junpeng Xing,Zhong Zheng,Zong Hou,Shu Liu
Cell membrane chromatography (CMC) has been widely recognized as a highly efficient technique for in vitro screening of active compounds. Nevertheless, conventional CMC approaches suffer from a restricted repertoire of cell membrane proteins, making them susceptible to oversaturation. Moreover, the binding mechanism between silica gel and proteins primarily relies on intermolecular hydrogen bonding, which is inherently unstable and somewhat hampers the advancement of CMC. Consequently, this investigation aimed to establish a novel CMC column that could augment protein loading, enhance detection throughput, and bolster binding affinity through the introduction of covalent bonding with proteins. This study utilizes polydopamine (PDA)-coated silica gel, which is formed through the self-polymerization of dopamine (DA), as the carrier for the CMC column filler. The objective is to construct the HK-2/SiO2-PDA/CMC model to screen potential therapeutic drugs for gout. To compare the quantity and characteristics of Human Kidney-2 (HK-2) cell membrane proteins immobilized on SiO2-PDA and silica gel, the proteins were immobilized on both surfaces. The results indicate that SiO2-PDA has a notably greater affinity for membrane proteins compared to silica gel, resulting in a significant improvement in detection efficiency. Furthermore, a screening method utilizing HK-2/SiO2-PDA/CMC was utilized to identify seven potential anti-gout compounds derived fromPlantago asiaticaL. (PAL). The effectiveness of these compounds was further validated using an in vitro cell model of uric acid (UA) reabsorption. In conclusion, this study successfully developed and implemented a novel CMC filler, which has practical implications in the field.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED THERMAL ENGINEERING
·
2024
·
IF 6.1
Lisheng Deng,Shusen lin,Linfa Xiao,Mitsuhiro Kubota,Hongyu Huang,Jun Li,Dezhen Chen
The application of MgO/Mg(OH) 2 in heat storage technology has been limited due to slow hydration rate and easy agglomeration. In this paper, nanoporous carbon particle (NCP) as a carrier was used to prepare NCP/MgO chemical heat storage composite materials by impregnation and calcination methods, respectively. The microstructure characterization, hydration reaction, and simultaneous thermogravimetric analysis experiments were carried out on the prepared composite materials. The results showed that the internal distribution of MgO in the composite material prepared by calcination method was more uniform, and the particle size of MgO was smaller. Under the conditions of 110 ℃ hydration temperature and 57.8 kPa water vapor partial pressure, the hydration conversion ratio of the composite material prepared by calcination method after 120 min of hydration conversion ratio reached 93 %, which was 17.7 % higher than that of the impregnated composite material and 50 % higher than that of pure MgO. Under the comprehensive influence of specific surface area, pore structure, and active component particle size, compared with pure materials and impregnated composite materials, the dehydration rate of the composite material prepared by calcination method at 300 ℃ was twice that of impregnated method and 6 times that of pure MgO, and the heat storage density reached 1039kJ/kg. After 10 cycles, the heat storage density still maintained an initial state of 95.8 %. Compared with pure materials and impregnated composite materials, NCP/MgO composite materials prepared by calcination method had better heat storage performance and higher cyclic stability.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Wei Liu,Ming Yang,Shuang Wang,Yan-Sai Bao,Yong-He Cui,Ling-Xu Meng,Liang-Cheng Li,Yang Wu,Yu-Yang Zhang
Solid-phase microextraction (SPME) has been widely used for the analyzing trace organic pollutants in environmental samples. The properties of coatings have a significant effect on the application range, selectivity and sensitivity of existing analytical methods. Therefore, the development of SPME technology depends on fibers with a stable, efficient, and selective coating. In this study, metal-organic frameworks (MOFs) were used to fabricate porous carbon membranes in situ for SPME. The composite material (UIO66-NH 2 @PAC) was directly carbonized to prepare a derivative porous carbon material (C-UIO66-NH 2 @PAC), which was applied to the extraction of off-odour organic pollutants for the first time. The Zr-N co-doping in the material was not only beneficial to the formation of derivatized porous carbon, but also endowed it with a certain hydrophilicity, which was highly advantageous for capturing weakly polar compounds. By optimizing the extraction and desorption conditions, a highly selective and sensitive analytical method was developed, which exhibited a detection limit of 0.61 and 0.78 ng L −1 for 2-methylisoborneol (2-MIB) and geosmin (GSM), respectively, along with a linear range from 10 to 3000 ng L −1 . Both intra-fiber repeatability (RSD 5.5 % and 3.7 %) and inter-fiber repeatability (RSD 9.7 % and 8.8 %) were satisfactory. The fiber coated with C-UIO66-NH 2 @PAC exhibited high extraction efficiency (the extraction efficiency of the analytes was 4.6–8.3 times higher than that of commercial fibers), and had excellent thermal and chemical stability. Finally, the C-UIO66-NH 2 @PAC-coated fibers were successfully applied to the SPME analysis of off-odour organic pollutants in real water samples, and these results highlighted the broad prospect for the detection of natural/drinking water.
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2024
·
IF 7.7
Lu Qin,Peng She,Panlong Si,Suqin Liu,Gaopeng Dai,Cong Pan
Photocatalytic production of H 2 O 2 is indeed a safe, sustainable and cost-effective technology, offering an environmentally friendly solution to the energy crisis through solar photocatalysis. However, it still faces challenges such as reliance on organic electron donors and pure O 2 , as well as inefficiencies in hole utilization. To overcome these limitations, a dual-channel photocatalytic system has been developed. In this study, we showcase the efficiency of the CuO/Cu(OH) 2 @g-C 3 N 4 composite, derived from CuBTC/g-C 3 N 4 via NaOH treatment, as a high-performance dual-channel photocatalyst for H 2 O 2 production. Under visible light (λ ≥ 420 nm), this composite achieves a H 2 O 2 yield of 1354 μmol/L in 120 min without any sacrificial agent, outperforming g-C 3 N 4 by 8.4 times, CuO by 13.6 times and CuO@g-C 3 N 4 by 1.9 times. Quenching experiments and electron paramagnetic resonance spectra confirmed that HO • and O 2 •− are intermediate products in the photocatalytic process, following a two-step single-electron reaction pathway. The superior activity of CuO/Cu(OH) 2 @g-C 3 N 4 in H 2 O 2 generation can be attributed to the synergistic effects of OH bonds on the CuO@g-C 3 N 4 Z-type heterojunction and Cu(OH) 2 . This research presents a straightforward and promising approach for developing highly efficient photocatalysts for energy conversion.
✓ 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）