Nanomedicine
·
2024
·
IF 4.7
Yumei Wang,Yue Zhou,Dongliang Zhai,Hao Deng,Xiaoliang Chen
Aim: Nano-hydroxyapatite (nHA) is a good nanocarrier to load 223Ra, but the low specific activity (sp.act.) of 223Ra@nHA limits its application in medicine. Methods: We proposed a method for preparing nHA using PEG as a template, which significantly increases the sp.act of 223Ra@nHA and a new method to loaded 99mTc for in vivo tracking. Results: The nHA synthesized using PEG as a template was associated with higher sp.act for 223Ra in comparison to nHA with identical particle size and without PEG. The nHA load 99mTc-MDP was associated with higher labeling rate and stability in comparison to 99mTc. Conclusion: All these findings suggest that using PEG as a template and 99mTc-MDP could be the most effective of synthetic 223Ra/99mTc@nHA.
研究领域:
纳米技术
·
放射药学
·
癌症治疗
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2015
·
IF 6.217
Tao Yang,Guojian Cao,Qingli Huang,Yanxia Ma,Sheng Wan,Hong Zhao,Na Li,Fujun Yin,Xia Sun,Dongen Zhang,Mingyan Wang
In present work, truncated octahedral Pt–Ni–Ir ternary nanoparticles with an average size of 10 nm and a Pt/Ni/Ir atomic ratio of 55/29/16 are synthesized through a facile method. Structural measurements show that the nanoparticles are surface Ni-scarce Pt–Ni–Ir ternary nanostructures . The mass activity and specific activity of the ternary catalyst are 511 mA mg −1 (Pt) and 1.03 mA cm −2 at 0.9 V (vs. reversible hydrogen electrode , RHE), respectively, which are nearly 4.8 and 6.0 times larger than that of the commercial Pt/C catalyst (106 mA mg −1 and 0.17 mA cm −2 ). After duration test of 10,000 cycles at the potential range from 0.6 to 1.0 V, the ternary catalyst preserved 66% and 73% of its initial mass activity and specific activity, respectively, which are 9 and 7.6 times that of the commercial Pt/C catalyst (37.2 mA mg −1 and 0.0998 mA cm −2 , respectively) after the same durability examination. The dramatic enhancement of Pt–Ni–Ir ternary catalyst can be attributed to its morphology, composition and nanostructure. Our research suggests that Pt–Ni–Ir ternary catalyst could be an excellent candidate for ORR . Our investigation might also spur increasing attention to tailoring morphology and composition of ternary or multi-metallic nanostructure with high electro-catalytic performance.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 56
·29925-29932
·
IF 3.708
Y. L. Li,X. L. Yang,C. X. He,X. L. Hu,J. Pu,L. Liu,G. B. Long,F. Liao
The maximum activities of fusion-tagged enzyme/mutants from cell lysates adsorbed by an anti-tag antibody immobilized in microplate wells were predicted to serve as equivalents of their specific activities for comparison with a six-histidine (6His)-tagged esterase and its tagged mutant as models. In brief, (a) a fixed quantity of a monoclonal anti-6His antibody was immobilized in microplate wells; (b) the maximum activity of a tagged enzyme/mutant from a cell lysate for saturation binding to the immobilized antibody (Vs) was predicted from the response of activities of the adsorbed tagged enzyme/mutant to quantities of total proteins in wells from the same lysate; and (c) Vs of tagged enzyme/mutants in lysates served as equivalents of their specific activities for comparison. Prediction of Vs of a tagged enzyme needed initial rates for absorbance changes of over 0.090 in 30 min, the highest occupancy of over 40% of binding sites of the immobilized antibody, and sufficient abundance of the tagged enzyme in lysates. With 0.6 μg antibody for immobilization in wells and total proteins of 10.0 to 128 μg from cell lysates, Vs of the tagged esterase had a coefficient of variation below 10% when the apparent specific activities in lysates varied more than four times. The ratio of Vs of the tagged esterase to the tagged mutant had higher precision and consistency with the ratio of their apparent specific activities from a large number of independent lysates. Hence, Vs predicted for tagged enzyme/mutants in cell lysates was suitable for comparison and may be applicable to verify positive mutants in a library.
研究领域:
生物化学
·
分子生物学
·
蛋白质工程
✓ 已验证
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2023
·
IF 7.5
Yu Chen,Zemin Zhao,Ze Li,Jieying Jing,Wenying Li
Hydrogenation saturation of phenanthrene was an effective method to acquire high energy density fuels. It is essential to design highly active and stable hydrogenation saturated catalyst to realize the above reaction. Herein, series of Ni-Co/NiAlOx catalysts were synthesized by reducing at different temperatures. Activity evaluation showed that the catalysts reduced at 560 °C (Cat-560) possessed a phenanthrene conversion amount of 8.0 mmol·g -1 active component·h −1 and 98% perhydrophenanthrene selectivity after running 6 h under 300 °C, 5 MPa. Furthermore, it was found that Cat-560 presented superior specific activity (4.3 mmol·kg −1 ·s −1 ) and TOF (41.1 × 10 −3 s −1 ) for symmetric octahydrophenanthrene hydrogenation (the rate determining reaction), and its specific activity was 3 times as high as that of the catalysts reduced at 520 °C The excellent hydrogenation performance of Cat-560 could be attributed to its special geometric and electronic structure. Characterization indicated that the Ni 2+ in Ni-Co/NiAlO X catalyst was mainly located in the nickel aluminum spinel octahedral sites, which was beneficial to the reduction of Ni and the formation of smaller Ni particles. Moreover, it was explored that the Ni d charge density of Cat-560 catalyst was −0.12 e, which was suitable for the adsorption and activation of phenanthrene and symmetric octahydrophenanthrene.
研究领域:
催化
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2018
·
IF 0
Tingting Liu,Bomin Feng,Xiuju Wu,Yanli Niu,Weihua Hu,Chang Ming Li
It is desirable yet challenging to develop highly active and durable hydrogen evolution reaction (HER) electrocatalysts with Pt-comparable activity for future energy devices. In this work, we report Ru2P nanoparticle decorated P/N dual-doped carbon nanofibers on carbon cloth (Ru2P@PNC/CC-900) as a highly efficient and durable hierarchical HER electrocatalyst in both acidic and alkaline media. Electrochemical tests show that this Ru2P@PNC/CC-900 possesses Pt-comparable HER activity to support 10 mA cm–2 HER current density at low overpotential of 15 and 50 mV in acidic and alkaline condition, respectively. Density functional theory calculations reveal that coupling Ru2P nanoparticles with heteroatom-doped carbon fibers leads to enhanced intrinsic HER activity. The integrative hierarchical architecture further endows high surface areas with good mechanical robustness to support abundant catalytically active sites and possesses excellent electrical conductivity and efficient access for mass transportation to facilitate the HER process.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Yuefei Wang,Yichao Gong,Man Yang,Jianqi Qi,Guojun Zhang,Tiecheng Lu
The advancement of Li 4 SiO 4 ceramics with enhanced performance represents a crucial research area within the domain of solid-state tritium breeding materials. However, the mechanical and physical properties of Li 4 SiO 4 are severely constrained by the challenge of balancing between densification and grain refinement. In this study, a ceramic with a high density and a distinctive cauliflower-like nanostructure is proposed. Specifically, Li 4 SiO 4 nanopowders with varying oxygen vacancy contents were obtained via the mechanical alloying process. The issues of low diffusivity and abnormal grain growth during the sintering of Li 4 SiO 4 ceramics were effectively addressed through the nonstoichiometrically activated sintering method. The resulting Li 4 SiO 4 ceramics exhibited a high relative density (90.21 % T.D.), exceptional mechanical strength (104 N), high thermal conductivity (2.98 W/m·K at room temperature and 1.91 W/m·K at 500 °C), and good ionic conductivity (4.20 × 10 −4 S/m). The findings indicated that the oxygen vacancies in Li 4 SiO 4 powders increased with the prolongation of the mechanical alloying period. This increase contributed to enhanced relative density, crushing load, and thermal conductivity of Li 4 SiO 4 ceramics, with only a slight decline in ionic conductivity. Concurrently, the oxygen vacancies in the ceramics were almost entirely annihilated by sintering under an air atmosphere. In conclusion, the utilization of nonstoichiometrically activated sintering offers significant advantages in the fabrication of tritium breeding ceramics with superior comprehensive characteristics.
研究领域:
材料科学
·
核能工程
·
固态物理
✓ 已验证
产品关联
DOI
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
·
2025
·
IF 3.7
Xiaotong Kang,Hang Yuan,Weimeng Li,Yun Hu,Fubao Sun
Thermophilic endoglucanases are of big promise in enzymatic degradation of lignocellulosic substrate, yet their limited catalytic efficiency remains a major barrier to industrial application. This study focused on the improvement of activity and stability of thermostable endoglucanase Dt CelA from Dictyoglomus turgidum with a three-stage cascade engineering strategy that integrated model-guided site-directed mutagenesis, disulfide bond introduction, and carbohydrate-binding module (CBM) fusion. Among the variants, the triple mutant S25D/T265C/A305C fused with CBM2 (S25D/T265C/A305C-A-CBM2) exhibited a 90.56 % increase in specific activity toward CMC relative to the wild type, together with a 2.97-fold longer half-life at 75 °C and a 5.3-fold longer at 80 °C. This mutant also displayed 3.0- and 5.4-fold higher hydrolytic activity against Avicel and konjac glucomannan, respectively. On natural lignocellulosic substrates including filter paper, sugarcane bagasse, and corn stover, the mutant also showed potential application. The mutated endoglucanase Dt CelA was powerful with enhanced catalytic performance and thermostability after multicascade engineering, which can provide a robust framework for the rational design of cellulases that are optimized for high-temperature biorefinery process.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Shuqi Hu,Zi-An Li
To further promote the widespread commercialization of proton exchange membrane fuel cells (PEMFCs), high performance oxygen reduction reaction (ORR) catalysts with high activity and stability must be developed to accelerate its sluggish kinetic process. Here, we report a successful synthesis of a novel hybrid material - highly synergistic PtCo nanoparticles (NPs) attached to three-dimensional graphene (PtCo @3DG). The PtCo @3DG exhibits excellent ORR performance, and the mass activity and specific activity measured at 0.9 V vs. RHE were 0.801 A/mg Pt and 1.250 mA/cm 2 respectively, which are 6.8 and 6.2 times higher than commercial Pt/C. High stability of this new material is achieved, which has demonstrated a loss of only 1.87% after an extensive 10,000 cycles test. The superior performance of PtCo @3DG can be primarily attributed to several key features, including its ultrathin size, a high Pt utilization, and a beneficial alloy effect. Additionally, the 3D graphene possesses an open and interconnected porous structure that facilitates efficient charge and mass transfer, which accelerates the desorption process of intermediates and exposes more active sites.
研究领域:
材料科学
·
电化学
·
纳米技术
·
能源材料
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2024
·
IF 3.7
Frank Peprah Addai,Jiacong Wu,Feng Lin,Xinnan Ma,Juan Han,Yuelin Liu,Yang Zhou,Yun Wang
In this work, a trimetallic (Ni/Co/Zn) organic framework (tMOF), synthesized by a solvothermal method, was calcinated at 400 and 600 °C and the final products were used as a support for lipase immobilization. The material annealed at 400 °C (Ni-Co-Zn@400) had an improved surface area (66.01 m2/g) and pore volume (0.194 cm3/g), which showed the highest enzyme loading capacity (301 mg/g) with a specific activity of 0.196 U/mg, and could protect the enzyme against thermal denaturation at 65 °C. The optimal pH and temperature for the lipase were 8.0 and 45 °C but could tolerate pH levels 7.0–8.0 and temperatures 40–60 °C. Moreover, the immobilized enzyme (Ni-Co-Zn@Lipase, Ni-Co-Zn@400@Lipase, or Ni-Co-Zn@600@Lipase) could be recovered and reused for over seven cycles maintaining 80, 90, and 11% of its original activity and maintained a residual activity >90% after 40 storage days. The remarkable thermostability and storage stability of the immobilized lipase suggest that the rigid structure of the support acted as a protective shield against denaturation, while the improved pH tolerance toward the alkaline range indicates a shift in the ionization state attributed to unequal partitioning of hydroxyl and hydrogen ions within the microenvironment of the active site, suggesting that acidic residues may have been involved in forming an enzyme–support bond. The high enzyme loading capacity, specific activity, encouraging stability, and high recoverability of the tMOF@Lipase indicate that a multimetallic MOF could be a better platform for efficient enzyme immobilization.
研究领域:
生物化学
·
材料科学
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CATALYSIS
·
2024
·
IF 6.5
Qiangqiang Xue,Zhengwen Li,Binhang Yan,Shafqat Ullah,Yujun Wang,Guangsheng Luo
A novel mesoporous SiO 2 encapsulated core-shell NiRh@NiO nanostructure was constructed to enhance the activity and stability of ethanol steam reforming (ESR). At 550 °C and ethanol-WHSV = 21 h −1 , the specific activity and conversion loss (17 h) of NiRh@NiO@m-SiO 2 were 0.42 mol ethanol /(g cat. ·h) and 10.9 %. The alloying of NiRh core, dominated NiO in shell, and abundant mesopore of SiO 2 were confirmed by systematic characterization techniques. The in situ DRIFTS results indicated that alloying Ni and Rh boosted ethoxide dehydrogenation to acetaldehyde and acetate demethanation to carbonate. ReaxFF molecular dynamics (MD) simulations suggested that NiO shell was conducive to water activation, which, in turn, promoted the conversion of CH x O y species. The SiO 2 encapsulation derived confinement effect inhibited both metal core sintering and leaching caused by the filamentous carbon. The abundant mesopores of SiO 2 ensured the facile in-diffusion of water and out-diffusion of carbonaceous products, suppressing carbon deposition within the SiO 2 encapsulation and the destruction of core-shell structure.
研究领域:
催化
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Advanced Materials Interfaces
·
2022
·Vol. 9
·期 7
·2101944
·
IF 6.389
Qianli Xing,Wei Yan,Chuangyu Wei,Zuoxu Xiao,Zhicheng Jin,Xue Liu,Jianwei Ren,Yanli Chen,Xiyou Li
The multidimensional PtZn quasi-cubic nanodendrites (PtZn-ND) with tremendous amounts of defectively coarse branches, having both highly active high-index facets and short-range (100) and (110) terraces resisted to sulfate, are synthesized via facile oil phase route at first time. The growth process is found to start from Pt nano-cuboid seeds, then PtZn nanoclovers which are formed from epitaxial growth, and then the flower-like PtZn crystals and finally the novel PtZn-ND. The formation mechanism of PtZn-ND, in particular the effects of hexadecyltrimethyammonium bromide (CTAB) and oleic acid (OA) on the morphology, crystal shape and exposure lattice facets, have been comparatively and systematically studied. And it turns out that CTAB mainly controls depositing directions, while OA mainly controls the crystal shape/size. The combination effect results in unique PtZn-ND structures. The novel PtZn-ND also displays superior catalytic performance and anti-sulfate poisoning ability. In particular, the mass activity (MA) and specific activity (SA) are 5.72 and 7.55 times higher than those of commercial Pt/C, and still 2.91 and 5.09 times higher after accelerated durability tests in 0.5 m H 2 SO 4 for oxygen reduction reaction.
研究领域:
材料科学
·
纳米技术
·
电化学
·
催化
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Chemistry
·
2022
·
IF 5.545
Qian Ningkang,Ji Liang,Li Xiao,Huang Jingbo,Li Junjie,Wu Xingqiao,Yang Deren,Zhang Hui
Combining the core-shell structure with the optimization of surface composition and structure in the shell is a fantastic strategy to enhance the electrocatalytic performances. Here, we synthesized trimetallic Au@PtxSny core-shell nanoparticles (NPs) with tunable composition and structure of Pt-Sn alloyed shells. Impressively, the Au@PtSn core-shell NPs with hexagonal PtSn alloyed shells exhibited the highest mass activity and specific activity toward ethanol oxidation reaction (EOR) in alkaline electrolyte, which are 13.0 and 12.7 times higher than those of the commercial Pt/C. In addition, the Au@PtSn core-shell NPs displayed the best stability compared to commercial Pt/C, with only 44.8% loss vs. 86.8% loss in mass activity after 1,000 s due to the stronger anti-poisoning ability for reaction intermediates. The theory calculations reveal that the introduction of Au core and alloying Pt with Sn both endow Pt with an appropriate d-band center, and thus effectively boosting the EOR activity.
研究领域:
材料科学
·
电化学
·
催化
✓ 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）