资源类型

期刊论文 135

年份

2024 1

2023 10

2022 8

2021 10

2020 14

2019 8

2018 14

2017 11

2016 4

2015 7

2014 6

2013 3

2012 6

2011 3

2010 6

2009 7

2008 4

2007 2

2006 1

2005 1

展开 ︾

关键词

无氢渗碳 2

G蛋白偶联受体 1

MOF基催化剂 1

PET酶 1

PET降解 1

Si/Al 比值 1

X射线自由电子激光 1

γ-氨基丁酸A型受体 1

三维含孔洞结构 1

不良妊娠结局 1

中微子 1

亲钠性铋基材料 1

人工智能 1

催化还原 1

共聚反应 1

切割效率 1

初始干密度 1

单萜 1

单质炸药 1

展开 ︾

检索范围：

排序： 展示方式：

Highly selective detection of copper(II) by a “ligand-free” conjugated copolymer in nucleophilic solvents

Weixing Deng, Pengfei Sun, Quli Fan, Lei Zhang, Tsuyoshi Minami

《化学科学与工程前沿（英文）》 2020年 第14卷 第1期   页码 105-111 doi: 10.1007/s11705-019-1791-6

摘要： The synthesis of -cyclohexyl carbamate-attached fluorene- -phenylene copolymer (PFPNCC) and the use of PFPNCC as a “ligand-free” fluorescent chemosensor for Cu(II) are described. Addition of Cu(II) can efficiently quench the fluorescence of PFPNCC in nucleophilic solvents such as DMF and DMSO, but not in low nucleophilic solvents such as 1,4-dioxane and THF. Ultraviolet-visible spectra of the mixture of the conjugated polymer and Cu(II) indicate the presence of a reduced Cu(I) ion in the solution. Furthermore, fluorescence recovery of PFPNCC observed at low temperature suggests that the quenching and reducing mechanism is most probably due to a photo-induced electron transfer from excited PFPNCC to Cu(II). Our findings provide a novel strategy for highly selective conjugated polymer-based chemosensors for various target analytes, albeit “ligand-free”.

关键词： ligand-free     fluorescent chemosensor     copper     photo-induced electron transfer    

HTML PDF 收藏

Effects of ancillary ligands in acceptorless benzyl alcohol dehydrogenation mediated by phosphine-free

《化学科学与工程前沿（英文）》 2023年 第17卷 第3期   页码 314-325 doi: 10.1007/s11705-022-2219-2

摘要： Acceptorless alcohol dehydrogenation stands out as one of the most promising strategies in hydrogen storage technologies. Among various catalytic systems for this reaction, cost-effective molecular catalysts using phosphine-free ligands have gained considerable attention. However, the central challenge for using non-precious metals is to overcome the propensity of reacting by one-electron pathway. Herein, we synthesized a phosphine-free η5-C5Me5-Co complex by using the metal–ligand cooperative strategy and compared its activity with analogous catalysts toward acceptorless alcohol dehydrogenation. The catalyst showed excellent performance with a turnover number of 130.4 and a selectivity close to 100%. The improved performance among the class of η5-C5Me5-Co complexes could be attributed to the more accessible Co center and its cooperation with the redox-active ligand. To further study the systematic structure-activity relationship, we investigated the electronic structures of η5-C5Me5-Co complexes by a set of characterizations. The results showed that the redox-active ligand has a significant influence on the η5-C5Me5-Co moiety. In the meantime, the proximal O−/OH group is beneficial for shuttling protons. For the catalytic cycle, two dehydrogenation scenarios were interrogated through density functional theory, and the result suggested that the outer-sphere pathway was preferred. The formation of a dihydrogen complex was the rate-determining step with a ΔG value of 16.9 kcal∙mol‒1. The electron population demonstrated that the η5-C5Me5 ligand played a key role in stabilizing transition states during dehydrogenation steps. This work identified the roles of vital ligand components to boost catalytic performance and offered rationales for designing metal–ligand cooperative nonprecious metal complexes.

关键词： acceptorless alcohol dehydrogenation     η5-C5Me5-Co     metal–ligand cooperation     theoretical calculation    

HTML PDF 收藏

Surface modification by ligand growth strategy for dense copper bismuth film as photocathode to enhance

《能源前沿（英文）》 doi: 10.1007/s11708-023-0893-5

摘要： Hydrogen production from photoelectrochemical (PEC) water splitting has been regarded as a promising way to utilize renewable and endless solar energy. However, semiconductor film grown on photoelectrode suffers from numerous challenges, leading to the poor PEC performance. Herein, a straightforward sol-gel method with the ligand-induced growth strategy was employed to obtain dense and homogeneous copper bismuthate photocathodes for PEC hydrogen evolution reaction. By various characterizations, it was found that the nucleation and surface growth of CuBi2O4 layer induced by 2-methoxyethanol ligand (2-CuBi2O4) demonstrated a decent crystallinity and coverage, as well as a large grain size and a low oxygen vacancy concentration, leading to the good ability of light absorption and carrier migration. Consequently, under simulated sunlight irradiation (AM1.5G, 100 mW/cm2), the 2-CuBi2O4 photocathode achieved an enhanced photocurrent density of −1.34 mA·cm−2 at 0.4 V versus the reversible hydrogen electrode and a promising applied bias photon-to-current efficiency of 0.586%. This surface modification by ligand growth strategy will shed light on the future design of advanced photoelectrodes for PEC water splitting.

关键词： copper bismuthate     photocathode     ligand growth strategy     dense film     PEC    

HTML PDF 收藏

Synthesis of vinylferrocene and the ligand-exchange reaction between its copolymer and carbon nanotubes

Ran SHI,Hai WANG,Ping TANG,Yuezhen BIN

《化学科学与工程前沿（英文）》 2014年 第8卷 第2期   页码 171-178 doi: 10.1007/s11705-014-1428-8

摘要： To improve the dispersibility of carbon nanotubes (CNTs), poly(vinylferrocene- -styrene) (poly(Vf- -St)), was grafted onto the surface of CNTs by a ligand-exchange reaction. Poly(Vf- -St) was obtained by a radical copolymerization reaction using styrene and vinylferrocene as the monomers. The vinylferrocene was synthesized from ferrocene via a Friedel-Crafts acylation. The molecular weight, molecular weight distribution, and amount of Vf in the poly(Vf- -St) were 1.32 × 10 , 1.69 and 17.6% respectively. The degree of grafting of the copolymer onto the CNTs surface was calculated from thermogravimetric analysis and varied from 27.1% to 79.7%. The addition of the poly(Vf- -St) greatly promoted the dispersibility of the modified CNTs in anhydrous alcohol. The electrical conductivity of composites prepared from the polymer-grafted CNTs and copolymer (acrylonitrile, 1,3-butadiene and styrene, ABS) strongly depended on the degree of grafting. These results show that the amount of polymer grafted onto the surface of CNTs can be controlled and that the electrical properties of composites prepared with these grafted polymers can be tuned.

关键词： vinylferrocene     poly (Vf-co-St)     CNTs     dispersibility    

HTML PDF 收藏

Effect of ligand chain length on hydrophobic charge induction chromatography revealed by molecular dynamics

Lin ZHANG, Yan SUN

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 456-463 doi: 10.1007/s11705-013-1357-y

摘要： Hydrophobic charge induction chromatography (HCIC) is a mixed-mode chromatography which is advantageous for high adsorption capacity and facile elution. The effect of the ligand chain length on protein behavior in HCIC was studied. A coarse-grain adsorbent pore model established in an earlier work was modified to construct adsorbents with different chain lengths, including one with shorter ligands (CL2) and one with longer ligands (CL4). The adsorption, desorption, and conformational transition of the proteins with CL2 and CL4 were examined using molecular dynamics simulations. The ligand chain length has a significant effect on both the probability and the irreversibility of the adsorption/desorption. Longer ligands reduced the energy barrier of adsorption, leading to stronger and more irreversible adsorption, as well as a little more unfolding of the protein. The simulation results elucidated the effect of the ligand chain length, which is beneficial for the rational design of adsorbents and parameter optimization for high-performance HCIC.

关键词： adsorption     desorption     irreversibility     protein conformational transition     molecular dynamics simulation    

HTML PDF 收藏

BGB-A445, a novel non-ligand-blocking agonistic anti-OX40 antibody, exhibits superior immune activation

《医学前沿（英文）》 doi: 10.1007/s11684-023-0996-8

摘要： OX40 is a costimulatory receptor that is expressed primarily on activated CD4+, CD8+, and regulatory T cells. The ligation of OX40 to its sole ligand OX40L potentiates T cell expansion, differentiation, and activation and also promotes dendritic cells to mature to enhance their cytokine production. Therefore, the use of agonistic anti-OX40 antibodies for cancer immunotherapy has gained great interest. However, most of the agonistic anti-OX40 antibodies in the clinic are OX40L-competitive and show limited efficacy. Here, we discovered that BGB-A445, a non-ligand-competitive agonistic anti-OX40 antibody currently under clinical investigation, induced optimal T cell activation without impairing dendritic cell function. In addition, BGB-A445 dose-dependently and significantly depleted regulatory T cells in vitro and in vivo via antibody-dependent cellular cytotoxicity. In the MC38 syngeneic model established in humanized OX40 knock-in mice, BGB-A445 demonstrated robust and dose-dependent antitumor efficacy, whereas the ligand-competitive anti-OX40 antibody showed antitumor efficacy characterized by a hook effect. Furthermore, BGB-A445 demonstrated a strong combination antitumor effect with an anti-PD-1 antibody. Taken together, our findings show that BGB-A445, which does not block OX40–OX40L interaction in contrast to clinical-stage anti-OX40 antibodies, shows superior immune-stimulating effects and antitumor efficacy and thus warrants further clinical investigation.

关键词： BGB-A445     OX40     agonistic antibody     OX40L noncompetitive    

HTML PDF 收藏

Cell-free systems in the new age of synthetic biology

Fernando Villarreal,Cheemeng Tan

《化学科学与工程前沿（英文）》 2017年 第11卷 第1期   页码 58-65 doi: 10.1007/s11705-017-1610-x

摘要： The advent of synthetic biology has ushered in new applications of cell-free transcription-translation systems. These cell-free systems are reconstituted using cellular proteins, and are amenable to modular control of their composition. Here, we discuss the historical advancement of cell-free systems, as well as their new applications in the rapid design of synthetic genetic circuits and components, directed evolution of biomolecules, diagnosis of infectious diseases, and synthesis of vaccines. Finally, we present our vision on the future direction of cell-free synthetic biology.

关键词： cell-free system     application    

HTML PDF 收藏

Fabrication of recyclable Fe chelated aminated polypropylene fiber for efficient clean-up of phosphate wastewater

《化学科学与工程前沿（英文）》 2023年 第17卷 第7期   页码 840-852 doi: 10.1007/s11705-022-2253-0

摘要： Herein, a Fe3+-loaded aminated polypropylene fiber has been reported as an efficient phosphate adsorbent. The remarkable phosphate removal ability of the fiber is due to Fe3+ immobilization, and it demonstrates a maximum adsorption capacity of 33.94 mg·P·g–1. Adsorption experiments showed that the fiber is applicable over a wide pH range from 2 to 9. Furthermore, the adsorption kinetics and isotherm data were consistent with the pseudo-second-order and Langmuir adsorption models, respectively. The adsorption equilibrium of the fiber for phosphate was reached within 60 min, indicating an efficient monolayer chemisorption process. Moreover, the adsorbent maintained prominent phosphate removal in the presence of competitive ions such as NO3– and Cl–, exhibiting high selectivity. More importantly, the fiber demonstrated excellent reusability (5 times) and low adsorption limit below 0.02 mg·P·g–1. In addition, the phosphate removal efficiency of the fiber can exceed 99% under continuous flow conditions. The adsorption mechanism was studied by X-ray photoelectron spectroscopy, showing that the adsorption of phosphate on the fiber mainly depended on the chemical adsorption of the modified Fe3+. Overall, this study proves that the fiber possesses many advantages for phosphate removal, including high adsorption efficiency, lower treatment limit, good recyclability, and environmental friendliness.

关键词： phosphate adsorption     aminated polypropylene fiber     Fe3+     ligand exchange     reusability    

HTML PDF 收藏

人工智能加速GPCR配体的发现 Review

陈伟, 宋驰, 冷梁, 张三印, 陈士林

《工程（英文）》 2024年 第32卷 第1期   页码 19-29 doi: 10.1016/j.eng.2023.09.011

摘要：

G蛋白偶联受体（GPCR）在多种生理过程中发挥着关键作用，是新药发现的重要靶标。然而，传统的GPCR配体发现方法需要投入大量的时间和资源。人工智能方法的出现为GPCR配体的识别和优化提供了有利的工具，改变了GPCR配体发现的研究方式。本文从数据资源、数据描述、模型设计等方面介绍了如何利用人工智能方法构建GPCR配体发现模型，并分析了人工智能方法在GPCR药物领域的应用；提出了一种基于人工智能方法整合多组学数据的GPCR配体筛选策略；探讨了人工智能方法在GPCR研究领域面临的挑战和未来发展方向。人工智能方法与多学科的交叉融合将提高GPCR配体发现的效率。

关键词： G蛋白偶联受体     配体     人工智能     多组学     药物发现    

HTML PDF 收藏

Recent advances in cycloaddition of CO with epoxides: halogen-free catalysis and mechanistic insights

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 1879-1894 doi: 10.1007/s11705-023-2354-4

摘要： The atom-economical cycloaddition of CO2 with epoxides to synthesize cyclic carbonates is a promising route for valuable utilization of CO2. Halogenide such as alkali metal halides and quaternary ammonium salt have been developed as the efficient catalysts. However, the spilled halogen causes equipment corrosion and affects the product purity. To address these concerns, the halogen-free cycloaddition of CO2 with epoxides has always been desired. In this review, we systematically discussed the halogen-free catalysis for cycloaddition of CO2 with epoxides from the mechanistic insights, aiming to promote the development of efficient halogen-free catalysts. Two types of catalysts, i.e., alternatives of halogen nucleophiles for epoxide activation, and bifunctional catalysts with Lewis acid-base sites for synergistic activation of CO2 and epoxides are summarized and emphasized. Specially, metal oxides as the potential halogen-free catalysts are highlighted due to their flexible acid-base sites for synergistic activation of CO2 and epoxides, facile preparation, and low cost.

关键词： carbon dioxide     halogen-free catalysis     cyclic carbonate     mechanistic insight    

HTML PDF 收藏

Hollow carbon spheres and their noble metal-free hybrids in catalysis

《化学科学与工程前沿（英文）》 2021年 第15卷 第6期   页码 1380-1407 doi: 10.1007/s11705-021-2097-z

摘要： Hollow carbon spheres have garnered great interest owing to their high surface area, large surface-to-volume ratio and reduced transmission lengths. Herein, we overview hollow carbon sphere-based materials and their noble metal-free hybrids in catalysis. Firstly, we summarize the key fabrication techniques for various kinds of hollow carbon spheres, with a particular emphasis on controlling pore structure and surface morphology, and then heterogeneous doping as well as their metal-free/containing hybrids are presented; next, possible applications for non-noble metal/hollow carbon sphere hybrids in the area of energy-related catalysis, including oxygen reduction reaction, hydrogen evolution reaction, oxygen evolution reaction, water splitting, rechargeable Zn-air batteries and pollutant degradation are discussed; finally, we introduce the various challenges and opportunities offered by hollow carbon spheres from the perspective of synthesis and catalysis.

关键词： hollow carbon spheres     functionalization     noble metal-free     catalysis    

HTML PDF 收藏

Decontamination of Cr(VI) facilitated formation of persistent free radicals on rice husk derived biochar

Kaikai Zhang, Peng Sun, Yanrong Zhang

《环境科学与工程前沿（英文）》 2019年 第13卷 第2期 doi: 10.1007/s11783-019-1106-7

摘要：

PFRs were produced on biochar during Cr(VI) decontamination.

PFRs formation on biochar was owing to the oxidization of phenolic-OH by Cr(VI).

Appearance of excessive oxidant led to the consumption of PFRs on biochar.

Biochar charred at high temperature possessed great performance to Cr(VI) removal.

关键词： Biochar     Persistent free radicals     Phenolic hydroxyl groups     Cr(VI) reduction    

HTML PDF 收藏

Thermoresponsive block copolymer supported Pt nanocatalysts for base-free aerobic oxidation of 5-hydroxymethyl

《化学科学与工程前沿（英文）》 2021年 第15卷 第6期   页码 1514-1523 doi: 10.1007/s11705-021-2092-4

摘要： A base-free catalytic system for the aerobic oxidation of 5-hydroxymethyl-2-furfural was exploited by using Pt nanoparticles immobilized onto a thermoresponsive poly(acrylamide-co-acrylonitrile)-b-poly(N-vinylimidazole) block copolymer, with an upper critical solution temperature of about 45 °C. The Pt nanocatalysts were well-dispersed and highly active for the base-free oxidation of 5-hydroxymethyl-2-furfural by molecular oxygen in water, affording high yields of 2,5-furandicarboxylic acid (up to>99.9%). The imidazole groups in the block copolymer were conducive to the improvement of catalytic performance. Moreover, the catalysts could be easily separated and recovered based on their thermosensitivity by cooling the reaction system below the upper critical solution temperature. Good stability and reusability were observed over these copolymer-immobilized catalysts with no obvious decrease in catalytic activity in the five consecutive cycles.

关键词： aerobic oxidation     base-free     5-hydroxymethyl-2-furfural     Pt nanoparticle     thermoresponsive block copolymer    

HTML PDF 收藏

Influence of the filler materials on flux-free brazing of pure aluminium (1050)

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA,

《机械工程前沿（英文）》 2010年 第5卷 第1期   页码 47-51 doi: 10.1007/s11465-009-0079-9

摘要： In the present study, samples of pure aluminium (1050) were deposited by cold spraying with filler materials such as Al12Si, Al7Si, Al12Si-4%Cu, and the Al-Si-based filler material A, which was especially developed for flux-free brazing by the Surface Engineering Institute. Besides, pure Si powder was also sprayed. The coated samples were heat-treated under different conditions and were brazed under an argon atmosphere without fluxes or with the flux Nokolok by an induction heating system. The shear strength of the brazed joints was determined. The results show that the filler materials could be well deposited by cold spraying. A thin layer of brittle Si could also form due to the strong deformation of the substrate surface. The heat treatments showed that a very good metallurgical bond between the filler materials and the substrate could be realized by the deposition by cold spraying. The Al7Si deposited samples could not be brazed without fluxes under the given conditions. The samples deposited with other filler materials could be brazed without fluxes. The in-situ diffusion process made it possible to braze the Si-deposited samples at 580°C. The joints of the samples deposited with the filler material showed the highest shear strength of 41 MPa, whereas the values of the Al12Si and Si deposited samples were less than 20 MPa. The employment of the flux Nikolok significantly increased the shear strength of the Al12Si deposited samples to more than 53 MPa.

关键词： aluminium     flux-free brazing     cold spraying     shear strength    

HTML PDF 收藏

New perspectives in free nitrous acid (FNA) uses for sustainable wastewater management

《环境科学与工程前沿（英文）》 2023年 第18卷 第2期 doi: 10.1007/s11783-024-1786-5

摘要：

● The historical development of free nitrous acid (FNA) technologies is reviewed.

关键词： Free nitrous acid     Acid-tolerant ammonia oxidizer     In situ generation     Wastewater management    

HTML PDF 收藏

标题 作者 时间 类型 操作

Highly selective detection of copper(II) by a “ligand-free” conjugated copolymer in nucleophilic solvents

Weixing Deng, Pengfei Sun, Quli Fan, Lei Zhang, Tsuyoshi Minami

期刊论文

Effects of ancillary ligands in acceptorless benzyl alcohol dehydrogenation mediated by phosphine-free

期刊论文

Surface modification by ligand growth strategy for dense copper bismuth film as photocathode to enhance

期刊论文

Synthesis of vinylferrocene and the ligand-exchange reaction between its copolymer and carbon nanotubes

Ran SHI,Hai WANG,Ping TANG,Yuezhen BIN

期刊论文

Effect of ligand chain length on hydrophobic charge induction chromatography revealed by molecular dynamics

Lin ZHANG, Yan SUN

期刊论文

BGB-A445, a novel non-ligand-blocking agonistic anti-OX40 antibody, exhibits superior immune activation

期刊论文

Cell-free systems in the new age of synthetic biology

Fernando Villarreal,Cheemeng Tan

期刊论文

Fabrication of recyclable Fe chelated aminated polypropylene fiber for efficient clean-up of phosphate wastewater

期刊论文

人工智能加速GPCR配体的发现

陈伟, 宋驰, 冷梁, 张三印, 陈士林

期刊论文

Recent advances in cycloaddition of CO with epoxides: halogen-free catalysis and mechanistic insights

期刊论文

Hollow carbon spheres and their noble metal-free hybrids in catalysis

期刊论文

Decontamination of Cr(VI) facilitated formation of persistent free radicals on rice husk derived biochar

Kaikai Zhang, Peng Sun, Yanrong Zhang

期刊论文

Thermoresponsive block copolymer supported Pt nanocatalysts for base-free aerobic oxidation of 5-hydroxymethyl

期刊论文

Influence of the filler materials on flux-free brazing of pure aluminium (1050)

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA,

期刊论文

New perspectives in free nitrous acid (FNA) uses for sustainable wastewater management

期刊论文