SEPARATION AND PURIFICATION TECHNOLOGY
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2023
·
IF 8.6
Yi Ren,Die He,Tong Wang,Hong Qi
Organosilica membranes with good hydrothermal stability are promising for pre-combustion capture, but the trade-off effect still constrains their gas separation performance. Herein, we prepared hybrid membranes by incorporating ZIF-7 nanoparticles into 1, 2-bis(triethoxysilyl)ethane (BTESE) networks to improve the H 2 /CO 2 permselectivity by the intrinsic properties of nanoparticles. The effect of inorganic fillers was investigated by adjusting the doping content of ZIF-7 nanoparticles. We found that the H 2 permeance of hybrid membranes remained at ∼10 −6 mol·m −2 ·s −1 ·Pa −1 , while the H 2 /CO 2 permselectivity decreased with increasing nanoparticle doping content. The E-ZIF-7-0.4 hybrid membrane showed H 2 permeance of 1.2 × 10 −6 mol·m −2 ·s −1 ·Pa −1 and H 2 /CO 2 permselectivity of 21.7. Our results may offer valuable insights into preparing hybrid membranes with optimal nanoparticle doping content.
研究领域:
材料科学
·
化学工程
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DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2016
·Vol. 408
·期 30
·8813-8820
·
IF 3.125
Fu Zhaofu,Li Gongke,Hu Yufei
A novel chemiluminescence (CL) system based on the reaction of fluorescent water-soluble nitrogen-rich quantum dots (N-dots) and diperiodatoargentate(III) (DPA) was developed. The prepared N-dots have a small size (≤10 nm) and high percentage of nitrogen (39.9 %), which exceeds the content of carbon in the same N-dots. The N-dots exhibit characteristic blue fluorescence under UV light and up-conversion luminescence. The relatively intense CL emission is based on the direct oxidation of N-dots by DPA. The CL emission may be attributed to the high nitrogen content and the special structure of the N-dots. The CL mechanism of N-dots and DPA was investigated by using CL, UV–Vis absorption, IR, fluorescence, and radical scavenging experiments. This investigation provides a way to study the optical properties of N-dots. The analytical applicability of the N-dots and DPA CL system in the determination of ferulic acid (FA) was explored. The CL intensity was linearly proportional to the concentration of ferulic acid from 3.0 × 10 −7 to 1.0 × 10 −5 g mL −1 with a detection limit of 8.0 × 10 −8 g mL −1 (3σ); the relative standard deviation was 2.4 % for 4.0 × 10 −7 g mL −1 FA ( n = 9). The proposed method was successfully applied to the determination of ferulic acid in Angelica sinensis . The study provides valuable insight into the role of nitrogen-rich quantum dots in CL.
研究领域:
分析化学
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生物化学
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产品关联
DOI
PubMed
高影响因子
Materials
·
2022
·Vol. 15
·期 12
·4149
·
IF 3.748
Yinghui Wang,Xiurong Guo,Danfeng Du,Shaochi Yang
Perovskite-type catalysts were widely used in the field of automobile exhaust purification due to their inherent physicochemical properties and excellent doping characteristics. A series of La1−xMxCo1−yNyO3(M = Ce, Ca; N = Fe, Mn) perovskite-type catalyst samples were prepared by sol-gel method for the four-way purification of PM, NOx, CO, and HC emitted by diesel exhaust. The activity of catalyst samples was tested by simulation experiments and hydrogen temperature-programmed reduction (H2-TPR). Catalyst samples were characterized by means of XRD, FT-IR, SEM, BET, and XPS analysis. The results demonstrated that the perovskite-type catalyst samples with a particle pore size of 3–5 μm can be prepared by sol-gel method. When A-site of LaCoO3perovskite-type oxide was doped by cerium ions, the catalyst samples produced small distortion. The doping of cerium ions to A-site was more conducive to the four-way purification of diesel exhaust than calcium ions. La0.8Ce0.2CoO3perovskite-type samples showed the best purification efficiency, and the purification efficiencies of PM, NOx, CO, and HC were 90%, 85%, 94%, and 100%, respectively. When the B-site of La0.8Ce0.2CoO3perovskite was doped with iron ions, the purification efficiency of catalyst samples for PM and NOxcan be further enhanced. When the B-site of La0.8Ce0.2CoO3perovskite was doped with manganese ions, the purification efficiency of the catalyst samples for PM can be further enhanced. It can be seen from the simulation experiments that La0.8Ce0.2Co0.7Fe0.3O3perovskite was the best doping amount, and the purification efficiencies of PM, NOx, CO, and HC were 95%, 92%, 94%, and 100%, respectively.Keywords:perovskite-type catalyst;diesel exhaust;sol-gel method;four-way purification;doping amount
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2020
·Vol. 187
·期 5
·1-11
·
IF 6.232
Zheng Xiaoke,Li Chenghui,He Yaqin,Wu Lan,Hou Xiandeng
In this work, a novel bi-modal imaging probe with enhanced CT contrast efficiency and FL brightness was constructed, in which the combination of a binary CT contrast agent BaHoF 5 and Cu-doped QDs served as a vehicle; hyaluronic acid (HA) was employed as a tumor-targeting ligand. With its CT contrast efficiency about 2.1- and 3.9-fold higher than PEG-BaHoF 5 and Iohexol, the CT contrast efficiency and the fluorescent brightness of the bi-modal probe were both enhanced. Likewise, its fluorescent brightness is almost 6-fold brighter after Cu-doped QDs loading. The most important contribution of this work lies on the proposed strategy. The inherent contradiction of the imaging sensitivity of CT and FL imaging is well balanced and a great CT/FL bi-modal imaging performance is simultaneously obtained even at low concentration (400 μg/mL) of the probe, which was superior to the previous CT/FL bi-modal probes. Moreover, since BaHoF 5 as a binary CT contrast agent was introduced instead of conventional Au and Bi 2 S 3 , the CT/FL bi-modal probe would be more suitable for different patients under different operation voltages. In addition, the in vitro tumor cell imaging also demonstrated a good photo-stability, FL brightness, and tumor-targeting capability of the probe, indicating its great potential in practical bi-modal imaging for further tumor diagnosis and therapy.
A novel bi-modal imaging probe with enhanced CT contrast efficiency and FL brightness was fabricated, in which its CT contrast efficiency was about 2.1- and 3.9-fold higher than PEG-BaHoF 5 and Iohexol, respectively, and its fluorescent brightness almost 6-fold brighter after Cu-doped QDs loading.
研究领域:
医学影像学
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纳米医学
·
肿瘤学
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产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2019
·Vol. 9
·期 4
·505
·
IF 4.034
Jieni Li,Henan Li,Dong Ding,Zibo Li,Fuming Chen,Ye Wang,Shiwei Liu,Huizhen Yao,Lai Liu,Yumeng Shi
We prepared high-performance photoresistors based on CH3NH3PbI3films with a high PbI2doping level. The role of PbI2in CH3NH3PbI3perovskite thin film was systematically investigated using scanning electron microscopy, X-ray diffraction, time-resolved photoluminescence spectroscopy, and photoconductive atomic force microscope. Laterally-structured photodetectors have been fabricated based on CH3NH3PbI3perovskite thin films deposited using precursor solution with various CH3NH3I:PbI2ratios. Remarkably, the introduction of a suitable amount of PbI2can significantly improve the performance and stability of perovskite-based photoresistors, optoelectronic devices with ultrahigh photo-sensitivity, high current on/off ratio, fast photo response speed, and retarded decay. Specifically, a highest responsivity of 7.8 A/W and a specific detectivity of 2.1 × 1013Jones with a rise time of 0.86 ms and a decay time of 1.5 ms have been achieved. In addition, the local dependence of photocurrent generation in perovskite thin films was revealed by photoconductive atomic force microscopy, which provides direct evidence that the presence of PbI2can effectively passivate the grain boundaries of CH3NH3PbI3and assist the photocurrent transport more effectively.Keywords:high PbI2doping content;PC-AFM;photoresistor;grain boundary passivation
研究领域:
材料科学
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光学工程
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产品关联
DOI
PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
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2017
·
IF 7.78
Tingting Gu,Wu Zou,Fuchun Gong,Jiaoyun Xia,Can Chen,Xuejiao Chen
As a new member of the carbon quantum-dot family, fluorescent nitrogen-rich quantum dots (NRQDs) were prepared by a mixed solvothermal method using 2-azidoimidazole and aqueous ammonia as reactants. These NRQDs are rich in nitrogen up to 40.2%, which are endowed with high fluorescence quantum yield , good photostability, water-solubility and favourable biocompatibility. We further explored the use of NRQDs combined with Cu 2+ as a nanoprobe for sensing fluorescently of cysteine (Cys) in complex biological samples. In this sensing system, the fluorescence is significantly quenched via energy transfer from NRQDs to Cu 2+ for the coordination of amino-containing groups with Cu 2+ . The strong affinity between Cu 2+ and Cys leads to the formation of Cu 2+ -Cys complexes and cause the detachment of Cu 2+ from the surface of NRQDs, thus the fluorescence of NRQDs recover. This nanoprobe allows analysis of Cys by modulating the switch of the fluorescence of NRQDs with a detection limit of 5.3 nM. As expected, the proposed NRQDs-Cu 2+ complex-based nanoprobes were successfully applied for the determination of Cys in human serum and plasma samples with recoveries ranging from 97.2% to 105.7%. The probe ensemble was also successfully applied to imaging of Cys in living cells with satisfactory results, which shows strong potential for clinical diagnosis.
研究领域:
分析化学
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生物医学工程
·
纳米技术
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DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
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2018
·
IF 2.746
Wu Zou,Fuchun Gong,Tingting Gu,Zhong Cao,Jiaoyun Xia
A facile approach was developed to prepare fluorescent nitrogen-rich quantum dots (NCQDs) using 2-azidoimidazole and ammonium hydroxide as reactants. The nitrogen and carbon elements of NCQDs form the frameworks of their nanostructures together and bear multiple active sites. By using NCQDs as fluorophores and graphene oxide (GO) as controllers, a hydrogen binding-based nanosensor was constructed for the detection of pyrophosphate (PPi). In NCQDs-GO sensing assemblies, the binding of GO to NCQDs results in the fluorescence quenching by FRET mechanism; while the addition of PPi leads to the fluorescence recovery of NCQDs because of the competitive binding between NCQDs and PPi to GO. The fluorescence intensity showed linearity with the added PPi concentration ranging from 0 to 400 μM with the detection limit of 8.3 nM (σ = 3). This procedure for the fabrication of amino-functionalized carbon quantum dots is simpler and more efficient compared to conventional doping and surface modification methods. The proposed NCQDs-GO sensing assemblies showed high selectivity and sensitivity to PPi over the competing anions in aqueous solution.
研究领域:
生物化学
·
分析化学
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产品关联
DOI
高影响因子
Journal of Environmental Sciences
·
2023
·
IF 6.9
Xiang Li,Limeng Wu,Aiqin Zhang,Shaohua Wu,Yan Lin,Chunping Yang
Switching the reaction routes in peroxymonosulfate (PMS)-based advanced oxidation processes have attracted much attention but remain challenging. Herein, a series of Co-N/C catalysts with different compositions and structures were prepared by using bimetallic zeolitic imidazolate frameworks based on ZIF-8 and ZIF-67 ( x Zn/Co-ZIFs). Results show that Co doping amount could mediate the transformation of the activation pathway of PMS over Co-N/C. When Co doping amount was less than 10%, the constructed x Co-N/C/PMS system ( x ≤ 10%) was singlet oxygen-dominated reaction; however further increasing Co doping amount would lead to the generation and coexistence of sulfate radicals and high-valent cobalt, besides singlet oxygen. Furthermore, the nitrogen-coordinated Co (Co-N X ) sites could serve as main catalytically active sites to generate singlet oxygen. While excess Co doping amount caused the formation of Co nanoparticles from which leached Co ions were responsible for the generation of sulfate radicals and high-valent cobalt. Compared to undoped N/C, Co doping could significantly enhance the catalytic performance. The 0.5% Co-N/C could achieve the optimum degradation (0.488 min −1 ) and mineralization abilities (78.4%) of sulfamethoxazole among the investigated Co-N/C catalysts, which was superior to most of previously reported catalysts. In addition, the application prospects of the two systems in different environmental scenarios (pH, inorganic anions and natural organic matter) were assessed and showed different degradation behaviors. This study provides a strategy to regulate the reactive species in PMS-based advanced oxidation process.
研究领域:
环境科学
·
催化化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Jichun Liu,Mingyuan Chi,Lianxin Li,Yuewen Zhang,Meng Xie
Mitochondrial dysfunction and metal ion imbalance are recognized as pathological hallmarks of Alzheimer's Disease (AD), leading to deposition of β-amyloid (Aβ) thereby and inducing neurotoxicity, activating apoptosis, eliciting oxidative stress, and ultimately leading to cognitive impairment. In this study, the red blood cell membrane (RBC) was used as a vehicle for encapsulating carbon quantum dots (CQD) and polydopamine (PDA), creating a nanocomposite (PDA-CQD/RBC). This nanocomposite was combined with near-infrared light (NIR) for AD treatment. The RBC offers anti-immunorecognition properties to evade immune clearance, PDA exhibits enzyme-mimicking activity to mitigate oxidative stress damage, and CQD acts as a chelating agent for metal ions (Cu 2+ ), effectively preventing Cu 2+ -mediated aggregation of Aβ. Furthermore, the local heating induced by near-infrared laser irradiation can dismantle the formed Aβ fibers and enhance the blood–brain barrier's permeability. Both in vitro and animal experiments have shown that PDA-CQD/RBC, in combination with NIR, mitigates neuroinflammation, and ameliorates behavioral deficits in mice. This approach targets multiple pathological pathways, surpassing the limitations of single-target treatments and enhancing therapeutic efficacy while decelerating disease progression.
研究领域:
神经科学
·
纳米技术
·
药学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TALANTA
·
2017
·
IF 4.162
Mei-Ling Chen,Shu-Chao Pang,Xue-Min Chen,Yi-Zhang,Lei Li
Developing a nanoscale drug delivery system with magnetic resonance imaging (MRI)/fluorescence imaging (FL) visibility to optimize the delivery efficiency and therapeutic efficacy under image guidance has attracted great attentions in the area of nanomedicine . Herein, a novel permeable yolk-shell structured gadolinium-doped quantum dots nanocomposite was synthesized as a theranostic nanocarrier via an indirectly doping method. The as-prepared permeable nanoparticles with tunable color fluorescent emission, paramagnetic and accessible mesoporous channels could be developed as a novel nanomedical platform for integrated multimodal diagnosis and therapy. The hydrophilic nanocomposites exhibited tunable fluorescence as well as high longitudinal relaxivity (r 1 = 17.32 mM −1 s −1 ) in water with good colloidal stability. In vivo animal experiments further verified CSSP could achieve FL/MRI dual modality imaging. The widely used antineoplastic anthracycline drug doxorubicin (DOX) was absorbed into the permeable nanospheres with 95.3% loading efficiency and released in a pH-sensitive pattern. In vitro cancer cell cytotoxicity tests verified that the DOX-loaded nanocomposites had enhanced cytotoxicity compared with free DOX at the same concentration. The as-prepared nanocomposites present great potential as MRI/FL-visible nanoscale drug carrier to realize imaging-guided personalized therapy.
研究领域:
纳米医学
·
药物递送系统
·
分子成像
·
癌症治疗
·
材料科学
✓ 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）