3D-hosted lithium metal anodes.

Lithium metal anodes are an appealing choice for rechargeable batteries due to their exceptionally high theoretical capacity of about 3860 mA h g-1. However, the uneven plating/stripping of lithium metal anodes leads to serious dendrite growth and low coulombic efficiency, curtailing their practical applications. The 3D scaffold/host strategy emerges as a promising approach that concurrently mitigates volume changes and dendrite growth. This review provides an overview of the regulating mechanisms behind scaffold/host materials for dendrite-free applications, tracing their historical development and recent progress across five key stages: material texture selection, lithiophilic modification, structural design, multi-strategy integration, and practical implementation. Additionally, scaffold/host materials are categorized based on their material texture, with a thorough examination of their respective advantages and drawbacks. Furthermore, this tutorial outlines the obstacles and complexities associated with implementing scaffold/host strategies. Finally, the determining factors that affect the electrochemical performances of scaffold/host materials are discussed, along with possible design criteria and future development prospects. This tutorial aims to provide guidance for researchers on the design of advanced scaffold/host materials for advanced Li metal anodes for batteries.

Synthesis of 2-amino-terephthalic acid crosslinked chitosan/bentonite hydrogel; an efficient adsorbent for anionic dyes and laccase.

This research article presents the fabrication of NH2-terephthalic acid crosslinked chitosan-bentonite composite, which adopted a facile synthesis approach and offered efficient adsorption capacity for organic dyes. A novel hydrogel material named CB 5:1 demonstrated remarkable adsorption for anionic dyes (Congo red (CR) and brilliant blue (BB)) while showing a negligible affinity for cationic dyes. Adsorption isotherm studies revealed the adsorption capacity of 4950 mg/g and 2053 mg/g (per g of composite's dry weight) for CR and BB following the Langmuir adsorption model. Kinetics and thermodynamic studies were also conducted while the adsorption of anionic dyes in the presence of metal ions, cationic dyes, anionic dyes, and in simulated water remained unaffected. Laccase, an industrially important enzyme, was also immobilized on CB 5:1 to achieve enzyme stability and reusability, resulting in a staggering immobilization capacity (4782 mg/g) at pH 6.0. Laccase immobilized product was employed to perform dye degradation (> 90 % for CR and > 75 % for BB), and the reusability was tested. Overall, our crosslinked product proved appealing for removing high concentrations of anionic organic dyes from polluted water and could be envisaged for practical use.

[Chemical Composition and Characterization of Nitroaromatic Compounds in Urban Areas of Shanghai].

The compositional characteristics, concentration of nitroaromatic compounds(NACs) in PM2.5 in urban Shanghai, and their correlation with gaseous precursors were investigated. A total of 39 winter and 46 summer PM2.5 samples from 2020 to 2021 were collected using a high-flow sampler and analyzed via ultra-performance liquid chromatography coupled with ESI-Orbitrap high-resolution mass spectrometry(UPLC-Orbitrap-HRMS). Quantitative analysis was performed on 12 NACs compounds, combined with backward trajectory meteorological elements, molecular composition, and classification analysis of CHON substances. The results showed that a total of 12 NACs had an average concentration in winter of 17.1 ng·m-3, which was three times higher than that in summer(5.7 ng·m-3), mainly due to air masses in winter coming primarily from the northern part of China with more biomass burning, whereas more air masses in summer came from the cleaner southeastern ocean. 4-Nitrophenol was the most abundant species of NACs in winter, whereas 4-nitrophenol(clean days) and 4-hydroxy-3-nitrobenzoic acid(polluted days) were the most abundant species in summer. Qualitative analysis based on features such as aromatic ring equivalence number(Xc), O/C, and H/C values for the identification and characterization of monocyclic and polycyclic aromatic compounds showed that CHON compounds were mainly aromatic compounds in winter and summer in urban Shanghai. The number and abundance of CHON compounds detected on PM2.5 polluted days were 2 and 1.5 times higher(winter) and 2.5 and 2 times higher(summer) than that on clean days, respectively. Comparing the analysis results of clean and polluted days in winter and summer, it was found that 80% of the CHON compounds with a relative abundance in the top 10 had O/N ≥ 3 and RDBE values between 5 and 8. The results suggest that these highly abundant CHON analogs may have had mononitro- or dinitro-substituted benzene rings. Correlation analysis between gaseous precursors and NACs indicated that oxidative reactive formation of VOCs(benzene, toluene, etc.) from anthropogenic emissions was the main source of NACs in summer. By contrast, it was influenced by a combination of biomass combustion emissions and secondary formation of oxidative NOx from anthropogenic VOCs in winter.

N-Rich and Sulfur-Doped Nano Hollow Carbons with High Oxidase-like Activity Prepared Using a Green Template of CaCO3 for Bacteriostasis.

Nanozymes, enzyme-mimicking nanomaterials, have attracted increasing attention due to their low cost, high stability, and catalytic ability compared with natural enzymes. However, the catalytic efficiency of the nanozymes is still relatively low, and catalytic reaction mechanisms remain unclear. To address these issues, herein we prepared nitrogen-riched and sulfur-codoped nano hollow carbons (N/S-HCS) using a green and useful template of CaCO3. N/S-HCS exhibits enhanced oxidase-like activity and catalytic kinetic performance. It could directly oxidize the colorless 3,3',5,5'-tetramethylbenzidine (TMB) to the heavy blue colored ox-TMB without H2O2. The maximum reaction rate (Vmax) is 186.7 × 10-8 M·s-1, and Michaelis-Menten constant (Km) is 0.162 mM. DFT results show that N and S codoping could work synergistically to provide more active sites, resulting in the superior ability to adsorb oxygen and enhanced catalytic activity. Meantime, we develop a multispectral characterization strategy to unravel catalytic reaction mechanisms about N/S-HCS. It successfully induces the generation of superoxide (•O2-) and hydroxyl (•OH) during the colorimetric reaction which are the key intermediate products of the catalytic reaction. Furthermore, N/S-HCS increased the cellular reactive oxygen species level significantly and induced bacteriostasis to more than 95% of Escherichia coli.

Unveiling alkali metal poisoning of CrMn catalyst for selective catalytic reduction of NOx with NH3: An experimental and theoretical study.

Alkali metal poisoning has been an intricate and unsolved issue confining the catalytic activity of NH3-SCR catalysts up to now. Herein, the effect of NaCl and KCl on catalytic activity of CrMn catalyst for NH3-SCR of NOx was systematically investigated to clarify the alkali metal poisoning by combined experiments and theoretical calculations. It unveiled that NaCl/KCl could deactivate CrMn catalyst due to the decrease in specific surface area, electron transfer (Cr5++Mn3+↔Cr3++Mn4+), redox ability and oxygen vacancy and NH3/NO adsorption. In addition, NaCl cut off E-R mechanism reactions by inactivating surface Brønsted/Lewis acid sites. DFT calculations revealed that (1) Na and K could weaken MnO bond, (2) competitive adsorption between Cl and NH3 was a main reason weakening Lewis acid, (3) Cl adsorption was also a major cause diminishing Brønsted acid and oxygen vacancy, (4) Both Na and K seriously impeded NO adsorption/activation, (5) NaCl/KCl increased the reaction heat of H2O desorption (rate-determining step) in E-R mechanism reactions and KCl elevated its energy barrier in L-H mechanism reactions. Thus, this study provides the deep understanding of alkali metal poisoning and a well strategy to synthesize NH3-SCR catalysts with outstanding alkali metal resistance.

Low-Spin Fe Redox-Based Prussian Blue with excellent selective dual-band electrochromic modulation and energy-saving applications.

Dual-band electrochromic materials (DBEMs) are of utmost importance for smart windows to realize independent control of the visible (VIS) and near-infrared (NIR) light. However, very few single-component DBEMs are capable of independently and effectively controlling both VIS and NIR light. Here, we present Prussian blue (PB) with remarkable performance to replace the composite DBEMs that require deliberate design and complicated preparation. Excellent durability and capacity were achieved simultaneously due to the activated low-spin Fe in PB. A dual-band electrochromic device (DBED) by using PB thin films as electrochromic layers was constructed, exhibiting superior dual-band electrochromic performance, energy storage performance and memory effect. We show that the energy-saving DBED can be bleached without applying any external bias potential, and can be colored by using a commercial photovoltaic solar panel under ambient solar irradiation. The stored energy during coloration can be further used to light up the lights. Finally, the coloration mechanism of the DBED was studied by the density functional theory calculations, to shed light on the large optical transmittance modulation in both VIS and NIR regions. The new insights will advance the design of efficient and durable DBEMs and the development of bi-functional smart windows.

Elucidating the facet-dependent reactivity of CrMn catalyst for selective catalytic reduction of NOx with NH3.

The facet-dependent reactivity of CrMn catalysts was still unclear, hindering the further enhancement of their low-temperature SCR performance. Herein, the facet-dependent reactivity of CrMn1.5O4 catalyst for NH3-SCR of NOx was innovatively illustrated by numerous characterizations and density functional theory (DFT) calculations. Exposed (100) facet of CrMn1.5O4 catalyst exhibited best low-temperature SCR activity with ≥90 % NO conversion within 148-296 °C and 2.86 × 10-3 mol/(g·s) reaction rate within 160-240 °C. The characterizations revealed that (100) facet could induce the increase of BET specific area, electron transfer, concentration of Mn4+ and Oα, surface acidity, redox ability, NH3 and NOx adsorption/activation capacity. Subsequently, DFT calculations demonstrated that (100) facet exhibited the strongest affinity for NH3 and NO due to its unique 3O3c-Mn5c-2O4c bond and abundant charges transfer near the active adsorption sites, and Brønsted acid and oxygen vacancies were most easily formed on (100) facet. Furthermore, H2O formation as the rate determining step easily occurred on (100) facet. Eventually, we successfully improved the low-temperature SCR activity of CrMn1.5O4 catalyst by further tailoring highly active (100) facet from 0.754 to 0.865. This work provides the deeper understanding of facet-dependent reactivity and a good strategy to improve the catalytic activity of the catalysts.

[Characteristics of Nitroaromatic Compounds in PM2.5 in Urban Area of Shanghai].

Nitroaromatic compounds (NACs) are an important class of nitrogen-containing compounds in fine particles. The investigation of characteristics and seasonal variation of NACs in PM2.5 increases our knowledge about nitrogen-containing compounds and contributes to the scientific basis in formulating reduction policies of NOx in urban areas. In this study, we analyzed the chemical composition of PM2.5 samples collected from March 2018 to February 2019 in an urban location in Shanghai. A total of 2439-3695 organic molecular formulas were detected using UPLC-Orbitrap MS. Nine NACs were quantified using an internal standard method. In spring, ρ(NACs) ranged from 3.12 to 16.76 ng·m-3, and the average concentration was 9.31 ng·m-3. In summer, it ranged from 1.05 to 9.70 ng·m-3, and the average value was 4.16 ng·m-3. In autumn, it ranged from 2.87 to 36.27 ng·m-3, and its average was 9.84 ng·m-3. In winter, it ranged from 4.83 to 56.23 ng·m-3, and the average was 22.37 ng·m-3. 4-Nitrophenol accounted for more than 25% of the quantified NACs in different seasons. In summer, the concentration of 5-nitrosalicylic acid accounted for 36%, but it decreased to 19% in winter. NACs in summer mainly originated from secondary formation, as evidenced by their clear correlation with the oxidant level, whereas biomass burning became the main source of NACs in winter.

Galactose-imidazole mediated dual-targeting fluorescent probe for detecting Fe3+ in the lysosomes of hepatocytes: Design, synthesis and evaluation.

In this work, three novel dual-targeting fluorescent probes were designed with modification by imidazole and one galactose (IM-Gal-1), by imidazole and two galactoses (IM-Gal-2), and by imidazole and three galactoses (IM-Gal-3), separately. These probes showed good selectivity and sensitivity toward Fe3+ with 1:2 stoichiometry recognition mode. The detection limits toward Fe3+ were (1.293 ± 0.005) × 10-7 M for IM-Gal-1, (7.735 ± 0.005) × 10-8 M for IM-Gal-2, and (1.325 ± 0.023) × 10-7 M for IM-Gal-3. These low-toxic probes exhibited excellent hepatic targeting capacity, which is attributed to the specific recognition of asialoglycoprotein receptor (ASGPR) overexpressed on hepatocytes by the galactose group of probes. The hepatic targeting capacity followed IM-Gal-1 < IM-Gal-2< IM-Gal-3 trend due to the galactose cluster effect. Under the attraction between acidic lysosome and basic imidazole group, these imidazole-modified probes were confirmed to possess good lysosome-targeting capacities, earlier demonstrating imidazole as a lysosome-targeting group. Overall, these dual-targeting probes co-modified by galactose and imidazole exhibited unique advantages in precise diagnosis and treatment of liver lysosomal iron-related diseases.

Engineering Z-scheme silver oxide/bismuth tungstate heterostructure incorporated reduced graphene oxide with superior visible-light photocatalytic activity.

Photocatalytic degradation of multiple organic contaminants has received extensive research attention and rational design of visible-light driven photocatalyst has been considered as an efficient approach. In this study, a visible-light Ag2O/Bi2WO6 heterostructure incorporated reduced graphene oxide (ABW-RGO) composite photocatalyst was prepared through a facile hydrothermal method for the first time and exhibited synergetic degradation behavior for contaminants in aqueous solutions. Under visible light, Tetracycline antibiotics has degraded 95.3% within only 40 min, and dye pollutants including Crystal Violet (cationic dye) and Congo Red (anionic dye) reached over 98.5% decomposition. The synthesized composite is also highly efficient in a wide pH range and multi-components system, maximizing the utilization of common sunlight, which make it suitable for industrial wastewater. The reactive oxidant species (ROS) experiment and electron spin resonance (ESR) measurement revealed the critical role of hydroxyl and superoxide radicals, clarifying the degradation pathway and mechanism analysis. The superior photocatalytic activity could be attributed to the formation of effective Z-scheme heterostructure and the excellent sorption capacity and conductivity of reduced graphene oxide. This research provides the design pathway to a novel catalyst using semiconductors composite and graphene support material, which can be extended to the energy-saving treatment of various organic pollutants.

Microwave hydrothermal fabrication of 3D hierarchical Br/Bi2WO6 with enhanced photocatalytic activity for Rhodamine B and tetracycline degradation.

Basing on the unique advantages of uniform and rapid volumetric heating of microwave irradiation, microwave hydrothermal method has been used to fabricate Br/Bi2WO6 for streamlining the preparation procedure and enhancing the photocatalytic activity. The results indicated that Br was successfully introduced into the lattice of Bi2WO6, which improved the absorption ability of visible light. Moreover, Br/Bi2WO6 exhibited smaller size and the enhanced separation efficiency of photogenerated carriers as compared with Bi2WO6. Br/Bi2WO6 exhibited superior reusability and photocatalytic activity of Rhodamine B (RhB) and tetracycline (TC). Furthermore, the enhanced photocatalytic activity of Br/Bi2WO6 was mainly ascribed to the increased specific surface area, wide UV-vis light absorption range, and high separation efficiency of photogenerated charge carriers originating from Br doping and microwave heating.

Carboxymethylcellulose-chitosan film modified magnetic alkaline Ca-bentonite for the efficient removal of Pb(II) and Cd(II) from aqueous solution.

In order to endow alkaline Ca-bentonite (ACB) with magnetic separation ability, simultaneously obtain better magnetic stability and stronger removal capacity of heavy metal cations; magnetic alkaline Ca-bentonite/carboxymethylcellulose-chitosan film (MACB/C-C) was prepared by organic modification of magnetic alkaline Ca-bentonite (MACB) using non-toxic carboxymethylcellulose and chitosan. Textural characterization results revealed that magnetic Fe3O4 nanoparticles were successfully immobilized on ACB and modified with C-C. The functionalized layer of C-C concurrently enhanced the stability of Fe3O4 and removal performances of heavy metal cations. Adsorption results indicated that MACB/C-C exhibited thorough separation from aqueous solution and greater uptake ability for Pb(II) and Cd(II) (483 mg·g-1 and 123 mg·g-1) than the nascent MACB (335 mg·g-1 and 76 mg·g-1), respectively, at pH 5 and 25 °C temperature. The adsorption of Pb(II) and Cd(II) on MACB/C-C mainly occurred via surface precipitation and complexation when pH > 2. MACB/C-C could be efficiently recycled with marginal decrease in adsorption capacity. The current approach credited to the convenient operation, simplified synthesis, and high efficiency of MACB/C-C could be deemed as a promising alternative for the removal of heavy metal cations from wastewater.

Light-Absorbing Pyridine Derivative as a New Electrolyte Additive for Developing Efficient Porphyrin Dye-Sensitized Solar Cells.

To fabricate efficient dye-sensitized solar cells (DSSCs), 4-tert-butylpyridine (TBP) is commonly used as an additive in the electrolytes for improving the photovoltages (VOC). However, TBP cannot play a positive role in improving the photocurrent (JSC) because of the lack of absorption in the visible-wavelength range. We herein report a light-absorbing pyridine derivative N1 as an additive for the axial coordination with porphyrin dyes. N1 was synthesized by introducing a (bis(4-methoxyphenyl)amino)anthryl moiety into the para-position of pyridine via an acetylene bridge, and porphyrin dye XW64 containing meso-3,5-disubstituted phenyl groups was synthesized considering that the meta-substituted phenyl groups may induce weaker steric hindrance with the axial pyridyl ligand, as compared with wrapped and strapped porphyrin dyes. Thus, N1 was used as an electrolyte additive together with TBP. When optimized concentrations of 6 mM N1 and 0.5 M TBP were used for fabricating DSSCs based on XW64, enhanced photovoltaic performance was achieved, with JSC, VOC, and efficiency of 15.65 mA·cm-2, 0.701 V, and 7.35%, respectively, superior to those of the corresponding DSSCs without using the additives (JSC = 14.86 mA·cm-2, VOC = 0.599 V, and efficiency = 5.94%). The enhancement of JSC can be ascribed to the improved light-harvesting ability induced by the axially coordinated N1. Furthermore, the two additives also can be used to fabricate efficient solar cells based on the wrapped porphyrin dye XW42, achieving high efficiency of 10.3%, indicative of their general applicability in fabricating high-performance DSSCs. These results indicate that the simultaneous employment of the traditional TBP additive and a pyridyl ligand with light-harvesting ability in the electrolyte for the axial coordination to a porphyrin dye is a promising approach for developing efficient DSSCs.

Expanded N-Confused Phlorin: A Platform for a Multiply Fused Polycyclic Ring System via Oxidation within the Macrocycle.

Novel interrupted π-conjugated macrocycles derived from expanded porphyrinoids were synthesized, and their unique reactivity was investigated in this work. The specific porphyrin analogs, so-called phlorins and isoporphyrins, possess a meso-sp3 methylene moiety, showing inner 3NH and 1NH pyrrolic cores, respectively, and extended near-infrared (NIR) absorption. Expanded N-confused pentapyrrolic phlorin analog 1 bears an interrupted cyclic π-conjugated system that is featured by a distinct higher HOMO and a lower LUMO. Oxidation of 1 allowed structural transformations through the expanded isoporphyrin-like species 2. One of the representative products is a spiro-carbon-bridged multiply N-fused product 3 comprising a fused [5.6.5.7.6.5]-hexacyclic ring obtained by oxidation with 2,3-dichloro-5,6-dicyano-p-benzoquinone. When magic blue was used as the oxidant, an aromatic N-confused pentaphyrin 4 was obtained via migration of one of the meso-phenyl groups to the ß-position of the neighboring pyrrolic ring. By employing the flexible cavity of 1 for metal coordination, Pd(II) complexation occurred with a specific meso oxygenation to give a bimetallic complex 5. In contrast to the rich oxidation reactions, reduction of 1 with NaBH4 resulted in the regioselective nucleophilic hydrogen substitution reaction at the para position of one of the meso-C6F5 groups. These results provide a practical approach for synthesizing novel interrupted or aromatic π-conjugated frameworks showing NIR absorptions.

Superior dye degradation and adsorption capability of polydopamine modified Fe3O4-pillared bentonite composite.

Owing to the increasing demand of environmentally benign materials for the degradation of hazardous dyes, herein we are reporting two different synthesis approaches for the fabrication of iron loaded bentonite composites by modifying and activating bentonite surface with polydopamine (PDA) followed by pillaring with Fe3+ (Fe-PDA-bentonite) and Fe3O4 (Fe3O4-PDA-bentonite). Both the composites were assessed for their adsorption and degradation performance using crystal violet (CV), Rhodamine B and Brilliant blue dyes following adopting advanced oxidation process type Fenton reaction under variable energy sources (Sunlight, UV light and Ultrasonication), concentration of H2O2 and catalyst dosage. Under UV light irradiation, the composites achieved complete degradation of the dyes within 60 min and showed degradation rate constant of 30.5E-3-81.8E-3. Textural characterizations of the composites were achieved via XRD, FTIR, TGA, XPS, SEM-EDX, TEM, N2 adsorption, VSM and UV/Vis spectrophotometry. The adsorption data of CV over the two composites fitted well with Langmuir adsorption isotherm, exhibiting the maximum adsorption capacity of 862 mg/g and 1235 mg/g for Fe-PDA-bentonite and Fe3O4-PDA-bentonite composites respectively. LCMS analysis of the post degradation products revealed that both the composites followed different degradation pathways and Fe3O4-PDA-bentonite showed superior photocatalytic performance by accomplishing complete dye degradation without leaving any degradation products. FTIR analysis of the post-degradation composites confirmed their structural stability with negligible iron leaching. This study, accredited to its cost-effectiveness, ease of operation and high efficiency, provides useful reference information for the degradation of dyes on industrial level.

Rational Synthesis of 5,5,5-Tricyclic Fused Thia-heptaphyrin (1.1.1.1.1.1.0) From a Helical Oligopyrrin Hybrid.

Oxidation of a thiophene-hexapyrrane hybrid S-P6 afforded a stable conjugated open-chain thiaheptapyrrolic helix 1 with the terminal thiophene and confused pyrrole units lying at a long distance that is adverse for further cyclization. Chelation of 1 with copper(II) ion afforded 1-Cu, which exhibits more distant terminal units. Interestingly, further oxidation of 1 triggered an intramolecular C-N fusion reaction to afford a unique 5,5,5-tricyclic fused linear thiaheptapyrrin 2, with the two terminals positioned in proximity, which favors the oxidative ring-closure reaction to give a unique 5,5,5-tricyclic fused thiaheptaphyrin (1.1.1.1.1.1.0) 3 under air. The inner-fusion strategy for positioning the reactive sites in proximity to promote oxidative cyclization offers a new approach for constructing large porphyrinoids through conjugated oligopyrrins without the assistance of metal ions.

Solvent Effects on the Symmetric and Asymmetric SN2 Reactions in the Acetonitrile Solution: A Reaction Density Functional Theory Study.

Bimolecular nucleophilic substitution (SN2) reactions are of great importance in chemistry and biochemistry due to their capability of constructing functional groups. In this work, we investigate the solvent effect on the free energy profiles of symmetric and asymmetric SN2 reactions in the acetonitrile solution using the proposed reaction density functional theory (RxDFT) method. This multiscale method utilizes quantum density functional theory for calculating intrinsic reaction free energy coupled with classical density functional theory for addressing solvation contribution. We find that the presence of acetonitrile brings both the polarization effect and solvation effect on the reaction pathways. For the eight selected symmetric SN2 reactions, the predicated reaction pathways agree well with the results from the direct and thermodynamic cycle (TC) methods with the SMD-M062X solvation model. In addition, the polarization effect reduces the free energy barriers by about 6 kcal/mol, while the solvation effect increases the barriers by about 18 kcal/mol. For the four selected asymmetric SN2 reactions, the predicted reaction pathways agree well with the results from the Monte Carlo simulations and experiments. The polarization effect and the solvation effect mutually reduce the free energy barriers, and the solvation effect plays a dominant role.

Immobilized metal affinity chromatography matrix modified by poly (ethylene glycol) methyl ether for purification of angiotensin I-converting enzyme inhibitory peptide from casein hydrolysate.

Purification of small bioactive peptides from complex biological samples is a difficult task due to the interference of concentrated large biomolecules. In this study, a magnetic immobilized metal affinity chromatography matrix modified by poly (ethylene glycol) methyl ether (IMACM@mPEG) was prepared and applied for the rapid purification of angiotensin I-converting enzyme (ACE) inhibitory peptides from casein hydrolysate. The proposed IMACM@mPEG considerably reduced the non-specific adsorption of large proteins and exhibited improved purification efficiency towards ACE inhibitory peptides. A novel peptide with moderate ACE inhibitory activity (IC50 value of 274 ± 5 µM) was identified as LLYQEPVLGPVR. Lineweaver-Burk plot confirmed the non-competitive inhibition pattern of LLYQEPVLGPVR. The purified peptide was digested after simulated gastrointestinal digestion and produced shorter peptides which contributed to enhanced ACE inhibitory activity. These results indicated that the IMACM@mPEG is an effective method for the prepurification of ACE inhibitory peptide and the purified peptide LLYQEPVLGPVR may have potential as nutraceutical ingredient in functional foods for hypertension treatments.

Ce regulated surface properties of Mn/SAPO-34 for improved NH3-SCR at low temperature.

Ce modified MnO x /SAPO-34 was prepared and investigated for low-temperature selective catalytic reduction of NO x with ammonia (NH3-SCR). The 0.3Ce-Mn/SAPO-34 catalyst had nearly 95% NO conversion at 200-350 °C at a space velocity of 10 000 h-1. Microporous SAPO-34 as the support provided the catalyst with increased hydrothermal stability. XPS and H2-TPR results proved that the Mn4+ and Oα content increased after incorporation of Ce, this promoted the conversion of NO at low temperature via a 'fast SCR' route. NH3-TPD measurements combined oxidation experiments of NO, NH3 indicated the reduction of both the surface acidity and the amount of acid sites, which effectively decreased the NH3 oxditaion to NO or N2O at elevated temperature and promoted the catalytic selectivity for nitrogen. A redox cycle between manganese oxide and Ce was assumed for the active oxygen transfer and facilitated the catalyst durability.

Effects of divalent copper on tetracycline degradation and the proposed transformation pathway.

To reveal the characteristics of tetracycline (TC) photocatalytic degradation under Cu(II) coexistence, effects of Cu(II) on TC photocatalytic degradation by ZnO nanoparticles (ZnO NPs) as a function of pH, humic acid (HA), and initial Cu(II) concentration were investigated. Interaction of TC with Cu(II) in the treatment process was analyzed by circular dichroism (CD) spectroscopy, while TC degradation pathway was investigated by high-performance liquid chromatography-mass spectrometry. Sixty-five percent and ninety-one percent TC degradation within 60 min in the absence and presence of Cu(II), respectively, was reported. Both adsorption and photocatalytic degradation of TC under Cu(II) coexistence increased with increasing pH from 3 to 6, while decreased with further increase in pH. HA inhibited the degradation of TC by ZnO NPs both in the presence as well absence of Cu(II), while TC degradation decreased from 91 to 73% and from 73 to 37% in the presence and absence of Cu(II), respectively. TC degradation by ZnO NPs first increased then decreased with increasing Cu(II). Maximum TC degradation (about 94%) was obtained in the optimum concentration range of Cu(II) (0.05-0.15 mmol/L). In addition, there was a lag effect between TC adsorption and degradation on ZnO NPs. TC degradation was improved via Cu(II)-TC surface complexation and followed N-demethylation and hydroxylation routes. This study could be of potential importance in extrapolating the transformation of TC or other antibiotics under the coexistence of heavy metals in water.