查找使用阿拉丁产品的科研文献

Noble-metal-free cobaloxime coupled with metal-organic frameworks NH2-MIL-125: A novel bifunctional photocatalyst for photocatalytic NO removal and H2 evolution under visible light irradiation

Shuang Luo,Xingyan Liu,Xiangjun Wei,Min Fu,Peng Lu,Xuan Li,Yiming Jia,Qiao Ren,Youzhou He

The novel bifunctional NH 2 -MIL-125/Co(dmgH) 2 composite catalysts with several different Co(dmgH) 2 contents that can simultaneously achieve photocatalytic NO removal and hydrogen production were first prepared by a simple and convenient method. The corresponding physical and chemical properties of the composite catalysts were characterized by SEM, XRD, ESR, in situ DRIFTS, etc. The characterization results indicated that the noble-metal-free Co(dmgH) 2 , which was much cheaper and more available than most noble-metals such as Pt, could be an effective co-catalyst to accelerate the separation of photogenerated electron-hole pairs, further eventually enhancing the photocatalytic efficiency. Under visible-light irradiation for half an hour, the NO removal ratio of NH 2 -MIL-125/Co(dmgH) 2 (3 wt%) increased by 22.7 % compared with the pristine NH 2 -MIL-125 without Co(dmgH) 2 loading. In addition, it was found that Eosin Y dye-sensitized NH 2 -MIL-125/Co(dmgH) 2 (3 wt%) was capable of promoting a hydrogen generation rate of 2195 μmol g −1 h -1 under visible light, which was 12.6 times greater than the original NH 2 -MIL-125. This strategy was expected as an available way to fabricate noble-metal-free molecular complexes with metal-organic frameworks (MOFs) to enhance the photocatalytic NO removal and hydrogen production performance simultaneously.

Time-resolved in-situ IR and DFT study: NH3 adsorption and redox cycle of acid site on vanadium-based catalysts for NO abatement via selective catalytic reduction

Hanzi Liu,Changfu You,Haiming Wang

Transient in-situ IR spectroscopy was performed to analyze the molecular behavior of selective catalytic reduction of NO with NH 3 on V 2 O 5 -WO 3 /TiO 2 catalyst. During NH 3 adsorption, an unexpected growth in the intensity of Lewis acid sites was observed due to the hydrogen migration, which was verified by the DFT calculation and the existence of intermediate species. The comparison between the isolated atmosphere experiments and the simultaneous exposure of NH 3 -NO-O 2 on catalytic monolayer demonstrated that: (i) there exists a pathway for Lewis to Brønsted acid sites transformation at T > 300 °C, (ii) the rate determining step of the SCR cycle involves in the re-oxidation of acid sites by O 2 at 200–300 °C. Generally, the Lewis acids are crucial at high temperatures, while Brønsted acids dominate the overall reaction at lower temperatures. Based on the experimental data and the DFT calculation, a mechanism for ammonia adsorption, acidity conversion and re-oxidation for the redox loop of the de-NOx reaction was proposed. The findings shed light on the understanding of relative strength of NO reduction and acid re-oxidation at different temperatures.

Enhanced SO2, NO, and Cr (VI) removal by lignin-derived high N-doped activated carbon through one-pot strategy: Structure development, structure–performance relationship and mechanism insight

Huirong Zhang,Lin Luo,Zixiong Zhao,Yi Shen,Jinglei Cui,Xiaokai Shi,Xiaoliang Han

The production of high-performance activated carbon (AC) is recognized as an essential strategy for the effective utilization of lignin resources. In this work, the N-doped AC was successfully prepared by blending sodium lignosulfonate (SL) and different ratios of FeCl 3 through one-pot strategy. The AC structure evolution and performance were obtained by a series of characterization and tests. The results showed that, during the activation process, FeCl 3 first complexed with urea and catalyzed the depolymerization of SL, and the rapid pore development was mainly caused by the template, including formed FeCl 2 , Na 2 Fe 3 Cl 8 and Na 6 FeCl 8 . The ratio of FeCl 3 /SL adjusts the AC physicochemical texture. AC-3 processed a super total specific surface area and pore volume, respectively up to 2048 m 2 /g and 1.47 cm 3 /g. Meanwhile, AC-2 showed a higher nitrogen content of 11.4 %. The as-prepared AC shows super desulfurization, denitrification and Cr (Ⅵ) removal ability. AC-2 displayed maximum sulfur capacity and NO conversion, up to 199.1 mg/g and 42.4 %. This enhanced performance is primarily attributed to the pore structure induced by FeCl 3 activation, which provides a foundation for adsorption and catalytic processes, further augmented by the increased active sites due to nitrogen doping. AC-3 achieved an extremely high Cr (VI) adsorption capacity, up to 386.2 mg/g, which was primarily attributed to the redox effect of N-containing and O-containing groups on Cr (VI), in addition, the effect of physical adsorption including pore structure is not neglectable. This study highlights the significant potential of environmentally friendly lignin-based porous carbon materials for removing contaminants in both gas and liquid phases.

Performance and Mechanism of Co and Mn Loaded on Fe-Metal-Organic Framework Catalysts with Different Morphologies for Simultaneous Degradation of Acetone and NO by Photothermal Coupling

Yuanzhen Li,Yinming Fan,Yanhong Wang,Yinian Zhu,Zongqiang Zhu,Shengpeng Mo,Xiaobin Zhou,Yanping Zhang

VOCs can be used instead of ammonia as a reducing agent to remove NO, achieving the effect of removing VOCs and NO simultaneously. Due to the high energy consumption and low photocatalytic efficiency required for conventional thermocatalytic purification, photothermal coupled catalytic purification can integrate the advantages of photocatalysis and thermocatalysis in order to achieve the effect of pollutants being treated efficiently with a low energy consumption. In this study, samples loaded with Co and Mn catalysts were prepared using the hydrothermal method on Fe-MOF with various morphologies. The catalytic performance of each catalyst was analyzed by studying the effects of their physicochemical properties through various characterizations, including XRD, SEM, BET, XPS, H2-TPR, TEM and O2-TPD. The characterization results demonstrated that the specific surface area, pore volume, high valence Co and Mn atoms, surface adsorbed oxygen and the abundance of oxygen lattice defects in the catalysts were the most critical factors affecting the performance of the catalysts. Based on the results of the performance tests, the catalysts prepared with an octahedral-shaped Fe-MOF loaded with Co and Mn showed a better performance than those loaded with Co and Mn on a rod-shaped Fe-MOF. The conversions of acetone and NO reached 50% and 64%, respectively, at 240 °C. The results showed that the catalysts were capable of removing acetone and NO at the same time. Compared with the pure Fe-MOF without Co and Mn, the loaded catalysts showed a significantly higher ability to remove acetone and NO simultaneously under the combination of various factors. The key reaction steps for the catalytic conversion of acetone and NO on the catalyst surface were investigated according to the Mars–van Krevelen (MvK) mechanism, and a possible mechanism was proposed. This study presents a new idea for the simultaneous removal of acetone and NOxby photothermal coupling.

Weitiao No. 3 increased isobutyric acid to enhance the effect of PD-L1 inhibitor on tumor growth and anti-tumor effect of CD8+T cells in gastric cancer

Zhu Hengzhou,Zhu Xiaodan,Huang Xiaona,Qian Yiyang,Li Jiahui,Zhang Jiaying,Niu Dong,Jin Chunhui

Gastric cancer (GC) is a prevalent malignancy worldwide with high morbidity and mortality. Its insidious onset and lack of sensitive early biomarkers impede routine screening, so most patients present advanced or metastatic disease at first diagnosis, leading to poor prognosis and scarce curative options. Surgery, chemotherapy and targeted therapy serve as standard GC treatments, however their efficacy is restricted by metastasis, adverse reactions and drug resistance, which drives the rapid development of immune checkpoint inhibitor (ICI)-based immunotherapy. Although monoclonal antibodies targeting programmed cell death protein 1/programmed cell death 1 ligand 1 (PD-1/PD-L1) resulted in significant survival benefits for GC patients, some patients exhibited an ineffective response. Our previous study has shown that Weitiao No. 3 (WD-3) enhanced the efficacy of anti-PD-1 immunotherapy by regulating intestinal flora in gastric cancer (GC) mice, in this study, huPBMC-NOG-dKO mice and MGC803 cells were used for in vivo and in vitro functional validation to explore the regulatory mechanism of WD-3 in GC immunotherapy. 16 S rRNA sequencing analysis of mouse fecal samples demonstrated that WD-3 significantly enriched the intestinal abundance of Lachnospiraceae and Ruminococcaceae in GC model mice. Targeted serum metabolomics further verified that WD-3 markedly elevated serum isobutyric acid level in GC mice. Combined with HE staining and tumor growth monitoring, both the intestinal flora mixture consisting of Lachnospiraceae and Ruminococcaceae and isobutyric acid prominently enhanced the anti-tumor efficacy of PD-L1 inhibitors in GC mice. Mechanistically, RNA sequencing and qRT-PCR assays identified ACOX2 as the most significantly up-regulated gene in isobutyric acid-treated MGC803 cells. Functional experiments using CCK-8 assay and flow cytometry revealed that isobutyric acid inhibited the viability and induced apoptosis of MGC803 cells, and such phenotypic changes were effectively rescued by ACOX2 knockdown. Furthermore, results from the CytoTox 96 cytotoxicity assay and ELISA revealed that combined treatment with isobutyric acid and PD-L1 inhibitor elevated the levels of LDH, IL-2, TNF-α, IFN-γ, Perforin 1 and GzmB, while suppressing IL-8, PD-1 and TIM-3 expression in CD8⁺ T cells co-cultured with MGC803 cells. Notably, all these regulatory effects were abrogated when MGC803 cells were transfected with si-ACOX2. These results suggested that WD-3 modulated intestinal flora to elevate isobutyric acid level, thereby enhancing the inhibitory effect of PD-L1 inhibitor on tumor growth and boosting the anti-tumor activity of CD8⁺ T cells by up-regulating ACOX2 expression in GC. These findings may provide novel targets for improving anti-PD-L1 therapy against GC.

Protonated NH2-MIL-125 via HCl vapor to introduce the moiety with charge and ample hydrogen as a novel bifunctional photocatalyst: Enhanced photocatalytic H2 production and NO purification

Shuang Luo,Chenghua Zhang,Xingyan Liu,Yue Li,Lei Tang,Min Fu,Song Wang,Jie Wu,Mengmeng Xu,Xiaoping Wang,Youzhou He

A novel protonated NH 2 -MIL-125 was fabricated to introduce the moiety with charge and ample hydrogen (–NH 3 + Cl - group) into NH 2 -MIL-125 using HCl vapor obtained by natural volatilization of hydrochloric acid as a protonating reagent, which could exhibit excellent photocatalytic activity in both hydrogen production and NO purification under visible light irradiation. The hydrogen production and NO purification rate of the best protonated NH 2 -MIL-125 were 6762.80 μmol g −1 and 49.17%, respectively, which were 20.53 and 1.84 times as that of the original NH 2 -MIL-125. A series of characterizations, such as Mott-Schottky, PL, FT-IR and in situ DRIFTS , etc. were used to characterize the photoelectrochemical properties of the optimal catalyst, which demonstrated the protonation effect can not only enhance the electron migration rate, but also effectively accelerate photo-generated electron-hole pairs separation in the photocatalytic reaction process. This research believed that using HCl vapor as a facile protonation reagent to introduce the moiety with charge and ample hydrogen (–NH 3 + Cl - ) was a very effective method to decorate MOFs for hydrogen evolution and NO removal.

Hyaluronic acid and polyvinyl alcohol-based radioresponsive hydrogel for combined radioimmunotherapy of breast cancer bone metastasis

Liubing Li,Zenghui Gu,Yanxian Wu,Subin Lin,Xiaju Cheng,Leshuai W. Zhang,Jianzhong Qin,Qirong Dong,Yong Wang,Yangyun Wang

Combining radiotherapy with immunotherapy holds promise for treating solid tumors and metastases, but challenges persist, including hypoxia-induced immunosuppression and immune-related adverse events from off-target toxicity. To address this, we engineered an in-situ formed hydrogel by crosslinking hyaluronic acid and polyvinyl alcohol with a reactive oxygen species (ROS)-responsive linker (3-aminophenylboronic acid). This hydrogel leverages radiotherapy-induced ROS within the tumor microenvironment to trigger localized release of nitric oxide (NO) and the toll-like receptor 7/8 (TLR7/8) agonist R848. NO normalizes hypoxic tumor vasculature, while R848 amplifies radiotherapy-initiated antitumor immunity. In breast cancer and bone metastasis models, this radioimmune-regulated hydrogel significantly enhanced tumor normoxia, promoted dendritic cell maturation, and primed CD8 + T cells, substantially improving the efficacy of combined radioimmunotherapy. Our study highlights a potent hydrogel-based strategy to overcome key limitations in advanced cancer therapy.

Ag/APTES/CuxO (x = 1, 2)-MGS-Coated No-Core Fiber Surface Plasmon Resonance Gas Sensor and Its Application in Hydrogen Sulfide Detection

Cheng Li,Liu Xiao,Xiaozhan Yang,Wenlin Feng

A comparative study on the activity and adsorption of bimetallic MOF-derived Me-Cu/TiO2 (Me=Fe, Co, Ni) for low-temperature selective catalytic reduction of NO by CO

Yong Shi,Xin Lan Ma,Jin Suo Gao,Feng Yun Yu,Chun Yan Li,Wei Xiong,Li Ping Huang

The catalytic activity, adsorption and synergistic effect over bimetallic MOF derivatives with different dopant metal were systemically compared. A series of Me-Cu/TiO 2 (Me=Fe, Co, Ni) derived from bimetallic Me/Cu-BTC MOFs were fabricated via a sacrificing template method and applied for CO-SCR. Among the bimetallic catalysts, Fe-Cu/TiO 2 presented the best low-temperature of nearly 100% NO conversion from 150 °C to 350 °C with good NO selectivity. For Me-Cu/TiO 2 (Me=Fe, Co, Ni), the productions of crucial Cu + intermediate were determined to be 51.17%, 50.45%,49.4% by XPS, which were consistent with their catalytic activity results. The superior redox behavior of Fe-Cu/TiO 2 can be attributed to its higher Oβ / (Oα +Oβ) ratio of 32.90% and the higher Me 2+ / Me 3+ ratio of 1.79. In situ infrared analysis revealed that the Fe doping not only improved the formation and stability of nitrate species, but also enhanced the quantity of Lewis acid sites by forming Cu + -CO. Furthermore, a possible low-temperature Langmuir-Hinshelwood (L-H) mechanism over Me-Cu /TiO 2 (Me=Fe, Co, Ni) was proposed.

Excellent low-temperature NH3-SCR of NO activity and resistance to H2O and SO2 over WaCeOx (a = 0.06, 0.12, 0.18, 0.24) catalysts: Key role of acidity derived from tungsten addition

Huansheng Tan,Shibo Ma,Xiaoyu Zhao,Yushi Li,Chen Zhao,Yujun Zhu

Bimetallic W a CeO x (a = 0.06, 0.12, 0.18, 0.24) catalysts were synthesized for selective catalytic reduction of NO x with NH 3 (NH 3 -SCR). The influences of W on structure, activity and surface properties were investigated by XRF, XRD, Raman, TEM, N 2 adsorption-desorption, H 2 -TPR, O 2 /NH 3 /SO 2 -TPD, XPS, and in-situ DRIFTS. The characterization results show that the W/Ce ratio has a great effect on the NH 3 -SCR activity. The different catalytic activities of W a CeO x are mainly attributed to the acidity change, especially the increase of B-acid content plays a major role in enhancing low temperature activity. W 0.18 CeO x exhibits excellent low-temperature NH 3 -SCR activity, SO 2 /H 2 O resistance and N 2 selectivity with a broad activity window (190–490 °C) with 5%H 2 O. Moreover, good activity window (235–460 °C) can be maintained even the catalyst treated with 5% H 2 O at 800 °C for 12 h, showing especial hydrothermal stability. Thus, it can be summarized that W 0.18 CeO x is regarded as outstanding catalyst for low-temperature NH 3 -SCR of NO.

Immunomodulatory activity of purified polysaccharides from Rubus chingii Hu fruits in lymphocytes and its molecular mechanisms

Xiaoyan Su,Ming Zhao,Xinyu Fu,Xiaodan Ma,Wei Xu,Songhua Hu

Polysaccharides from Rubus chingii Hu fruits (RFPs) were extracted, purified, characterized and investigated for immunomodulatory activity. Results indicated that RFPs were heteropolysaccharides with molecular weight of 51.7 kDa and contained carbohydrate contents of 96.83%. RFPs with characteristic absorptive peaks of polysaccharide structure and α-configuration were composed of mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, arabinose and fucose with a molecular ratio of 0.08:0.17:0.16:0.48:5.73:1.00:1.79:0.03. RFPs promoted splenocyte proliferation, NO release, cytokine production and intracellular Ca 2+ concentration. The mechanism underlying splenocyte activation by RFPs was elucidated by RNA-Seq, in which 2214 differentially expressed genes (DEGs), 2030 GO terms and 92 KEGG pathways were identified. RFPs were further proved to induce a balanced Th1/Th2/Th17 response pattern through MAPK, NF-κB, Jak-STAT and Calcium signaling pathways in splenocytes. These findings provided a fundamental basis for the further application of RFPs as immunomodulators in food and medicine.

Uptake Kinetics of \({\text{NH}_{4}^{+} }\), \({\text{NO}_{3}^{-} }\) and \({\text{H}_{2}\text{PO}_{4}^{-} }\) by Typha orientalis, Acorus calamus L., Lythrum salicaria L., Sagittaria trifolia L. and Alisma plantago-aquatica Linn

Kunlun Wang,Qian Hu,Yumin Wei,Hui Yin,Changhong Sun,Guizhong Liu

The emergent plants may differ in their capacity to assimilate nutrients from eutrophic water bodies, so the utilization of suitable emergent plants is the key part for successful restoration of shallow eutrophic lakes and rivers. This research applied the depletion method to study the kinetics of uptake of nutrient (H2PO4−,NH4+,NO3−) in different nutrient stresses by the five emergent aquatic plants (Acorus calamusL.,Typha orientalis, Lythrum salicariaL.,Sagittaria trifoliaL.,Alisma plantago-aquaticaLinn) in the riverine zones of Dashi River (39°30′–39°40′ N, 115°59′–116°5′ E), a shallow eutrophic river located in Fangshan District, Beijing. The results showed that at the three phosphorus levels,A. calamusandA. plantago-aquaticahad the highest maximum uptake rate values forNH4+under low to moderate phosphorus conditions, and high phosphorus, respectively.T. orientalishad the highest maximum uptake rate values forNO3−at all phosphorus concentrations, while the Michaelis-Menten constant values ofL. salicariaandA. plantago-aquaticawere smaller. At the three nitrogen levels, the maximum uptake rate values forH2PO4−were the greatest forA. plantago-aquaticaat the low to moderate nitrogen levels andL. salicariaat high levels. Meanwhile,T. orientalisandL. salicariahad the smallest Michaelis-Menten constant values. In this study, nitrogen microbial transformations, such as nitrification, denitrification and their coupling were not measured and their role in measuring kinetics was not assessed. Thus, achieved results shall be considered as a synthesis of several processes mediated by plants, a theoretical guidance to the selection of plant species for phytoremediation of polluted water bodies with different nutrient stresses for quality improvement around the diverse rivers in Haihe River basin.Keywords:emergent plants;eutrophication;nitrogen;phosphorus;uptake kinetics;stress