查找使用阿拉丁产品的科研文献

Facile Preparation of Pd/UiO-66-v for the Conversion of Furfuryl Alcohol to Tetrahydrofurfuryl Alcohol under Mild Conditions in Water

Yanliang Yang,Dongsheng Deng,Dong Sui,Yanfu Xie,Dongmi Li,Ying Duan

The hydrogenation of furan ring in the biomass-derived furans is of great importance for the conversion of biomass to valuable chemicals. Fabrication of high activity and selectivity catalyst for this hydrogenation under mild conditions was one of the focuses of this research. In this manuscript, UiO-66-v, in which vinyl bonded to the benzene ring, was first prepared. Then, the uniformly distributed vinyl was used as the reductant for the preparation of Pd/UiO-66-v. The catalyst was characterized by X-ray diffraction, thermogravimetric, N2physical adsorption/desorption, X-ray photoelectron spectroscopy, scanning electron microscope, transmission electron microscopy, energy dispersive spectrometer elemental mappings, and inductively coupled plasma atomic emission spectroscopy to find the Pd/UiO-66-v had a narrow palladium nanoparticles size of 3–5 nm and maintained the structure and thermal stability of UiO-66-v. The Pd/UiO-66-v was used for the hydrogenation of furfuryl alcohol to tetrahydrofurfuryl alcohol in water. 99% conversion of furfuryl alcohol was obtained with 90% selectivity to tetrahydrofurfuryl alcohol after reacted at 0.5 MPa H2, 303 K for 12 h. The Pd/UiO-66-v was proved to be effective for the hydrogenation of furan ring in furans and could be used for at least five times.Keywords:furfuryl alcohol;hydrogenation;tetrahydrofurfuryl alcohol;Pd/UiO-66-v;water solvent

Enhanced denitrification performance of Alcaligenes sp. TB by Pd stimulating to produce membrane adaptation mechanism coupled with nanoscale zero-valent iron

Zeyu Wang,Cong Chen,Huan Liu,Dzmitry Hrynshpan,Tatsiana Savitskaya,Jianmeng Chen,Jun Chen

The microbial reduction of nitrate in the presence of nanoscale zero-valent iron (nZVI) was evaluated to assess the feasibility of employing nZVI for biological denitrification treatment. The effect of modified nZVI on the growth, metabolism, and denitrification performance of Alcaligenes sp. TB under aerobic conditions was studied. Results showed that Alcaligenes sp. TB with nZVI/Pd had 31.5% increase in nitrate removal and 18.1% decrease in nitrite accumulation within 28 h. nZVI/Pd exhibited less inhibition on the cell growth (OD 600  = 0.725), NADH/NAD + ratio (86% of control), and electron transfer system activity (68.5% of control). In addition, nZVI/Pd decreased the membrane fluidity by increasing the trans/cis isomerization ratio (317.7% of control) to enhance the resistance of nZVI. This study underlines the effects of nZVI/Pd on membrane susceptibility via membrane fatty acid transformation during denitrification and suggests the influence of engineered nanomaterials on denitrification.

Combination of an autophagy inhibitor with immunoadjuvants and an anti-PD-L1 antibody in multifunctional nanoparticles for enhanced breast cancer immunotherapy

Cheng Yibin,Wang Caixia,Wang Huihui,Zhang Zhiwei,Yang Xiaopeng,Dong Yanming,Ma Lixin,Luo Jingwen

Background The application of combination therapy for cancer treatment is limited due to poor tumor-specific drug delivery and the abscopal effect. Methods Here, PD-L1- and CD44-responsive multifunctional nanoparticles were developed using a polymer complex of polyethyleneimine and oleic acid (PEI-OA) and loaded with two chemotherapeutic drugs (paclitaxel and chloroquine), an antigen (ovalbumin), an immunopotentiator (CpG), and an immune checkpoint inhibitor (anti-PD-L1 antibody). Results PEI-OA greatly improved the drug loading capacity and encapsulation efficiency of the nanoplatform, while the anti-PD-L1 antibody significantly increased its cellular uptake compared to other treatment formulations. Pharmacodynamic experiments confirmed that the anti-PD-L1 antibody can strongly inhibit primary breast cancer and increase levels of CD4+ and CD8+ T cell at the tumor site. In addition, chloroquine reversed the “immune-cold” environment and improved the anti-tumor effect of both chemotherapeutics and immune checkpoint inhibitors, while it induced strong immune memory and prevented lung metastasis. Conclusions Our strategy serves as a promising approach to the rational design of nanodelivery systems for simultaneous active targeting, autophagy inhibition, and chemotherapy that can be combined with immune-checkpoint inhibitors for enhanced breast cancer treatment.

Quercetin/Anti-PD-1 Antibody Combination Therapy Regulates the Gut Microbiota, Impacts Macrophage Immunity and Reshapes the Hepatocellular Carcinoma Tumor Microenvironment

Ruoxia Wu,Jiaqing Xiong,Ting Zhou,Zhen Zhang,Zhen Huang,Sha Tian,Yongli Wang

Objective: The use of immune checkpoint inhibitors (ICIs) provides promising strategies for hepatocellular carcinoma (HCC) treatment. This study aimed to explore impact and underlying mechanism of the combination therapy of quercetin and anti-programmed cell death 1 (anti-PD-1) antibody on HCC. Methods: Orthotopically transplanted HCC tumors in mice were treated with quercetin, anti-PD-1 antibody, or a combination of both therapies. Histopathological changes and programmed cell death ligand 1 (PD-L1) expression were characterized by hematoxylin and eosin (H&E) and immunohistochemistry (IHC) staining. The diversity and differences of gut microbiota (GM) were evaluated through 16S rRNA sequencing. Levels of macrophage immunity-related cytokines were quantified by enzyme-linked immunosorbent assay (ELISA), quantitative real-time polymerase chain reaction (RT-qPCR), and Western blot. Results: Combination therapy reduced necrosis, fibrosis, and PD-L1 expression in liver tissues. Additionally, combination therapy reduced GM imbalance and increased abundance of Firmicutes, Actinobacteria, and Verrucomicrobiota at the phylum level as well as Dubosiella and Akkermansia at the genus level. Combination therapy improved macrophage immunity, raised the expressions of CD8a, CD4, CD11b, interleukin (IL)-10, and interferon (IFN)-γ , and declined the expressions of IL-4, IL-6, toll-like receptor 4 (TLR4), an inhibitor of nuclear factor κBα (IκBα), and the NFκB subunit p65. Upon combination therapy, expressions of M2 macrophage-related genes arginase-1 (Arg-1), IL-10, transforming growth factor-β (TGF-β), and matrix metalloproteinase-9 (MMP-9) were upregulated. Instead, M1 macrophage-related genes IL-6, IL-12a, IL-1β, and tumor necrosis factor-α (TNF-α) were downregulated. Conclusions: Quercetin/anti-PD-1 antibody combination therapy reshaped HCC tumor microenvironment in mice in parallel with regulating the GM and macrophage immunity.

The cellular immunotherapy of integrated photothermal anti-oxidation Pd–Se nanoparticles in inhibition of the macrophage inflammatory response in rheumatoid arthritis

Chuping Zheng,Aiping Wu,Xinyun Zhai,Hong Ji,Zhikang Chen,Xu Chen,Xiyong Yu

Reducing the inflammatory response is a major goal in the therapy of rheumatoid arthritis (RA). Herein, we integrated palladium nanoparticles (Pd NPs) with selenium nanoparticles (Se NPs) and obtained a multiple nanosystem ( [email protected] NPs) that could simultaneously scavenge hydroxyl radicals (⋅OH) and provide a photothermal effect. The [email protected] NPs were constructed by a simple self-assembly method in which Se NPs were electrostatically bonded to Pd NPs; hyaluronic acid (HA) was linked to the NPs by ester bonding to provide macrophage targeting ability. The experiments show that the combined therapy of eliminating ⋅OH with Se NPs and utilizing PTT with Pd NPs could effectively reduce the inflammatory response in macrophages more effectively than either individual NP treatment. In addition, the outer layer of HA could specifically target the CD44 receptor to enhance the accumulation of [email protected] NPs at the lesion, further enhancing the therapeutic effect. After treatment for 15 days, the [email protected] NPs nearly eliminated the inflammatory response in the joints of mice in an induced RA model, and prevented joint damage and degradation.

A Novel Strategy for the Preparation of Supported Pd as an Efficient Catalyst for the Hydrogenation of Nitrobenzene in Mild Conditions

Zhi Hu,Yiyi Cheng,Meng Wu,Ying Duan,Yanliang Yang,Tianliang Lu

An advanced strategy was developed for the synthesis of molecular sieve-supported Pd catalysts. In this method, reductant containing C=C was in-situ prepared and pre-dispersed in the pore of the zeolites. The C=C group in the reductant can reduce the Pd2+to Pd0efficiently, leading to the formation of small and uniform Pd nanoparticles (~2 nm). The physical and chemical properties of the catalyst were characterized by XRD, TEM, XPS (ICP-OES), N2isothermal adsorption-desorption, and H2-TPR. These catalysts showed high catalytic performance for the hydrogenation of nitrobenzene to aniline. All the TOFs for 1.5 Pd/Y, 1.5 Pd/ZSM-5, and 1.5 Pd/MOR with 1.5 wt% Pd loading are higher than 1000 h−1at 30 °C and 0.1 MPa H2. Meanwhile, kinetic analysis for 2.0 Pd/Y was carried out, and an apparent activation energy of 28.88 kJ mol−1was obtained, which is lower than most of the reported values in the literature. Furthermore, these catalysts were stable and recyclable.Keywords:Pd;in-situ reduction;hydrogenation;molecular sieve

Novel Dual-Mode NIR-II/MRI Nanoprobe Targeting PD-L1 Accurately Evaluates the Efficacy of Immunotherapy for Triple-Negative Breast Cancer

Wan-Ling Liu,Yong-Qu Zhang,Xiang-Jie Luo,Yuan-Yuan Zhu,Liang Song,Zi-He Ming,Li-Xin Zhang,Meng-Jun Li,Rui-Chan Lv,Guo-Jun Zhang,Min Chen

Pd nanoparticles supported on porous N-doped carbon derived from ZIF-8: a facile and efficient catalyst for reduction of nitrophenols

Tang Yukuai,Chen Su,Liang Yusheng,Han Fengyan

We report a facile strategy to prepare the Pd nanoparticles loaded on porous N-doped carbon by direct carbonization of zeolitic imidazolate framework (ZIF-8) at 1000 o C. ZIF-8 not only serves as a precursor for N-doped carbon but also provides a framework to confine Pd nanoparticles with small size. The resulting Pd/ZIF-8(1000) has a regular morphology and excellent catalytic activity towards the reduction of nitrophenols (2-NP, 3-NP, and 4-NP) at room temperature with NaBH 4 as a reductant in aqueous solution. The enhanced performance is mainly due to N-doping, uniform dispersion and average size (2.3 nm) of Pd nanoparticles, large surface area, and synergistic effect between the metals (Pd NPs) and the support. Moreover, Pd/ZIF-8 (1000) remains the activity even after the 10th recycle experiment, indicating the catalyst has good stability. Importantly, ZIF-8(1000) can be applied as a framework to support highly uniform and stable noble metals with small size.

Pd nanoparticles supported on microflower NiMOF modified roughed nickel foam with the enhanced active site for electrochemical dechlorination of trichloroacetic acid

Fangyuan Wang,Yuanyuan Li,Huanqing Xie,Chunyu Wu,Wen Gao,Jianping Qiu,Lexing You,Shuang Song

Electrocatalytic hydrodechlorination (ECH) has been considered as an effective method to convert refractory chlorinated organics into biodegradable chlorine-free organics under mild conditions. In this work, a composite electrode of Pd/NiMOF/roughed nickel foam (Pd/NiMOF/RNF) with excellent dechlorination performance was prepared by electrodeposition of Pd nanoparticles on the flower-shaped NiMOF interlayer grown in-situ . Benefiting from the high specific surface area of NiMOF structure and excellent dispersion of Pd facilitated, the Pd/NiMOF/RNF offered abundant active hydrogen and larger open channels for the easy diffusion of reactants and products in the electrochemical dechlorination process. 97% of 6 μmol/L trichloroacetic acid (TCAA) was dechlorinated at a cathodic potential of −1.2 V within 90 min. The corresponding palladium mass activity was calculated to be 0.39 μg min −1 cm −2 mg −1 Pd, which was approximately 3.5 times greater than other report on ECH cathode. Moreover, the Pd/NiMOF/RNF cathode remained stable even after five consecutive cycle tests. Toxic assessment results indicated that the dechlorination process was beneficial to the detoxification of TCAA at the end of reaction. The hydrodechlorination mechanism of TCAA was proposed by density functional theory (DFT) analysis and electrochemical characterization on the Pd/NiMOF/RNF electrode. The findings of this study have the potential to contribute to the development of electrocatalytic treatment methods for chlorinated organic compounds in drinking water.

Electrocatalytic upcycling of polyethylene terephthalate plastic to formic acid coupled with energy-saving hydrogen production over hierarchical Pd-doped NiTe nanoarrays

Hugang Zhang,Yile Wang,Xinmiao Li,Kai Deng,Hongjie Yu,You Xu,Hongjing Wang,Ziqiang Wang,Liang Wang

Electrochemical upcycling of plastic waste to high-value chemicals is an ideal approach for the valorization of waste resources. In this study, we report the electro-reforming of polyethylene terephthalate (PET) plastic hydrolysate to valuable formate and hydrogen. Pd-deposited hierarchical aligned NiTe nanoarrays on Ni foam (Pd-NiTe/NF) is developed for oxidation of PET hydrolysate at anode and hydrogen evolution at cathode, with the overpotentials of 0.019 and 1.35 V at 10 and 100 mA cm -2 , respectively. In co-electrolysis system, the Pd-NiTe/NF exhibits high Faradaic efficiencies for concurrent production of value-added formate (95.6%) and H 2 (98.6%). The high activity and stability of Pd-NiTe/NF can be ascribed to that the interfacial heterostructures by incorporating Pd atoms and the strongly interfacial electronic interactions of between Pd and NiTe can synergistically promote PET-derived ethylene glycol to formate oxidation and hydrogen evolution. This work shows promising prospect in electro-reforming PET plastic waste to valuable chemicals.

In Situ Observations of Shell Growth and Oxidative Etching Behaviors of Pd Nanoparticles in Solutions by Liquid Cell Transmission Electron Microscopy

Ting Su,Zhong Lin Wang,Zhiwei Wang

It is demonstrated that the redox reaction behaviors of Pd nanoparticles in HAuCl 4 solutions can be substantially modified by the introduction of hexadecyl trimethyl ammonium bromide (CTAB) agents through systematic liquid cell transmission electron microscopy (LCTEM) investigations. The gradual dissolution of Pd nanoparticles is observed when HAuCl 4 solution is pumped into liquid flow cells, the etching characteristics of which are depended on both HAuCl 4 concentrations and incident electron doses. In comparison, with the presence of CTAB agents, the dominated phenomenon appears to be the precipitation of Au species and incorporation onto the surface of Pd seeds. It is also observed that the rapid growth of Au on Pd seeds occurs by loading Pd and HAuCl 4 solutions into static liquid cells. The resultant Au shells exhibit rather sparse structural configurations and are formed possibly by homogeneous nucleation/coalescence of Au species as well as monomer attachments. The observed Au-shell growth instead of Pd dissolution is attributed to the presence of the residual regents, which may be also responsible for the initially already existing small Au adsorptions at the corner/edge sites of Pd seeds. The study provides a useful reference for the convenient fabrication of complex nanostructures and functional nanomaterials in a controllable way.

Cellulosic protic ionic liquids hydrogel: A green and efficient catalyst carrier for Pd nanoparticles in reduction of 4-nitrophenol in water

Xiang Li,Fuping Dong,Lihua Zhang,Qinqin Xu,Xianyi Zhu,Songmiao Liang,Lijie Hu,Haibo Xie

The design and fabrication of functional hydrogel materials for environmental catalysis is a frontier topic both in fields of material science and catalysis. In this study, a new cellulosic hydrogel anchoring 1,1,3,3-tetramethyl guanidinium–based ionic liquids moiety (CHI) was firstly prepared by simply adding bicyclic anhydrides into newly developed 1,1,3,3-tetramethyl guanidine/DMSO/CO 2 solvent system for cellulose. The presence and amount of bicyclic anhydrides as a cross linker was proved to be an important factor for the hydrogel formation. And then, Pd nanoparticles (NPs)@CHI composites were fabricated by the reduction of the absorbed Pd(II) ions on CHI using NaBH 4 as reducing agent. The samples were characterized by techniques of 1 H NMR, 13 C NMR, FT-IR, SEM, TEM, EDX, XPS, XRD and ICP-OES analysis. It was identified that the CHI presented good immobilization capacity of Pd NPs, and the achieved Pd NPs@CHI composite had high catalytic activity and excellent reusability for the reduction of 4-nitrophenol in water. The activation parameters of the reduction reaction of 4-nitrophenol catalyzed by Pd NPs@CHI using NaBH 4 were calculated as Ea = 10.8 kJ mol −1 , ΔH #  = 8.1 kJ mol −1 and ΔS #  = −234.8 J mol −1  K −1 .