Publications by authors named "Liuchun Zheng"

In this study, an innovative approach for the integrated monitoring, optimization and control of the combined ozonation (O) and powdered activated carbon (PAC) adsorption process is introduced making use of spectral surrogates (UVA and EEM-PARAFAC components). The combined O-PAC process is designed to remove organic micropollutants (µP) from secondary effluent. Therefore, the removal of 6 µP with varying ozone reactivity was systematically studied in both O and PAC as stand-alone systems and in the combined O-PAC system.

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Polyureas have been widely applied in many fields, such as coatings, fibers, foams and dielectric materials. Traditionally, polyureas are prepared from isocyanates, which are highly toxic and harmful to humans and the environment. Synthesis of polyureas via non-isocyanate routes is green, environmentally friendly and sustainable.

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The excellent combined properties of poly(butylene succinate) (PBS) make it a promising biodegradable plastic. However, the lack of functionality and low impact strength limit its application. Poly(dimethylsiloxane) (PDMS) was introduced to prepare new high-performance and functional poly(butylene succinate)--poly(dimethylsiloxane) (PBS--PDMS) in this work.

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Natural cellulose is one of the most important substances coexisting on the surface of pyrite. Oxidation of pyrite produces hydroxyl radicals (•OH). In this study, a pyrite-cellulose binary system was constructed with natural cellulose to investigate the effect of cellulose on the mechanism of •OH generation via oxidation of pyrite, and the mechanism for abiotic oxidative •OH production by pyrite under the influence of cellulose was investigated with oxidation and quenching experiments and characterization techniques.

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The introduction of long-chain branched structures into biodegradable polyesters can effectively improve the melt strength and blow-molding properties of polyesters. In this study, pentaerythritol (PER) was used as a branching agent to synthesize branched poly(butylene dodecanedioate) (PBD), and the resulting polymers were characterized by Nuclear Magnetic Resonance Proton Spectra (H NMR) and Fourier Transform Infrared spectroscopy (FT-IR). It was found that the introduction of a small amount of PER (0.

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In response to Cd, Pb, and Cu pollution in acid mine drainage (AMD), a multigroup cellulose material (TCIS) containing thiol (-SH), carboxyl (-COOH), and imine (-C = N) groups was prepared through oxidation and grafting reactions. At pH 5, the maximum Cd(II), Pb(II), and Cu(II) adsorption performances of TCIS were 53.60, 120.

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Novel poly(butylene succinate-butylene furandicarboxylate/polyethylene glycol succinate) (PBSF-PEG) was synthesized using two-step transesterification and polycondensation in the melt. There are characterized by intrinsic viscosity, GPC, H NMR, DSC, TGA, tensile, water absorption tests, and water degradation at different pH. GPC analysis showed that PBSF-PEG had high molecular weight with average molecular weight () up to 13.

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Oil pollution is causing deleterious damage to aquatic ecosystems and human health. The utilization of agricultural waste such as corn stalk (CS) to produce biosorbents has been considered an ecofriendly and efficient approach for removing oil. However, most previous studies focused on the modification of the whole CS, which is inefficient due to the heterogeneity of CS.

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A series of non-isocyanate poly(ether urethane) (PEU) were prepared by an environmentally friendly route based on dimethyl carbonate, diols and a polyether. The effect of the chemical structure of polyurethane hard segments on the properties of this kind of PEU was systematically investigated in this work. Polyurethane hard segments with different structures were first prepared from hexamethylene di-carbamate (BHC) and different diols (butanediol, hexanediol, octanediol and decanediol).

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Three-dimensional (3D) self-assembled quantum dot (QD) aerogels have attracted attention due to the combined properties of both QDs and porous materials. However, the difficulty and complexity of structural composition control limit the practical application of 3D self-assembled QDs. Hence, convenient, available and multifunction QD aerogels need to be explored to promote broader practical applications.

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TEMPO-NaDCC-oxidized cellulose (TNOCS) with a large surface area and an abundance of carboxyl groups was used to remove heavy metal ions (Cd, Cu, and Pb) and their organic acid complexes [HM-OAs] (OAs, i.e., citric acid (CA) and propionic acid (PA)), and then reveal their adsorption behaviors.

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A cationic monofunctional platinum anticancer drug, phenanthriplatin (PhenPt(II)), exhibits promising anticancer effect on various cancer cell lines. Unlike the conventional platinum(II) drugs, PhenPt(II) is more likely to bind the N7 adenosine base of DNA in situ, and consequently resulting in a unique cellular response profile and unusual potency. However, since this drug is positively charged, it can easily bind to plasma protein that leads to rapid systematic clearance and deleterious toxicities, which greatly limits its in vivo application.

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Cancer resistance has been the huge challenge to clinical treatment. A photothermal therapy of second near-infrared (NIR-II) organic dye small molecule has been used to conquer the cancer resistance. However, the available NIR-II dye lacks selectivity and spreads throughout the body.

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In view of the characteristics of heavy metal and antibiotic compound pollution in the Pearl River Basin in Guangzhou. More scientifically modified cellulose, named HVUC, is characterized by multiple hydrophilic groups, long chains and large space and displays highly efficient adsorption of both Cd and sulfamethoxazole (SMZ) and good adaptability in a wide pH range and at high ion strength. Furthermore, the coadsorption mechanism was elaborated from multiple angles.

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2,2,6,6-Tetramethylpiperidine-1-oxyl (TEMPO) was oxidized to produce TEMPO-oxidized cellulose (TOCS) with a nanofunctionalized surface and abundant carboxyl groups. In a batch experiment, three pH values (2, 5 and 7), three modes (single, binary and multiple systems), and systems with inorganic and organic materials were applied to explore the adsorption of coexisting metals and antibiotics on TOCS. The adsorption capacity of TOCS was substantially influenced by these factors, and the adsorption behaviors were also different in these systems.

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The development of efficient and sustainable sorbents for emergent oil cleanup has attracted tremendous attention. In this study, the feasibility of enzymatic grafting of octadecylamine (ODA) on corn stalk pith (CSP) by laccase-TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) treatment for enhanced oil-water separation was investigated. The dynamic contact angle tests suggest that the modified CSP (LCSP) had higher hydrophobicity (WCA, 157.

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A new self-assembled cellulose (SACS) containing multi-functional amine, carboxyl and hydroxyl groups was successfully obtained through etherification, cross-linking and grafting processes. Then, the adsorption of sulfamethoxazole (SMZ) and Cd(II) onto SACS at pH values of 3, 5.7 and 7.

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Low interfacial adhesion seriously limits the wide application of PBO fiber in composites. To solve this problem, a novel hierarchical reinforcement strategy was developed by introducing epoxy sizing, nanoreinforcement of amino-functionalized silicon dioxide (SiO-NH), and an interfacial compatibilizer of 2,6-bis(2-hydroxy-4-aminophenyl) benzobisoxazole (HABO) onto poly(p-phenylene benzobisoxazole) (PBO) fibers via a facile dip-coating approach. SiO-NH and HABO were uniformly dispersed in epoxy sizing, forming an active interface layer.

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Article Synopsis
  • Researchers developed phosphorus-containing stalk cellulose (PFC) from corn stalks to effectively adsorb antibiotics sulfamethoxazole (SMZ) and sulfadiazine (SD), achieving maximum adsorption capacities of 1.385 mg/g and 2.527 mg/g at a neutral pH of 7.
  • The adsorption efficiency was significantly influenced by pH levels, with a preference for SD over SMZ, driven by the interaction between charged species and the PFC.
  • Advanced theoretical methods like density functional theory (DFT) and molecular dynamics (MD) simulations were used to study the adsorption mechanism, revealing important structural factors and interactions that contribute to the stability and effectiveness of PFC in adsorbing these antibiotics.
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In this work, we developed a facile end-functionalization method using hydroxylated coumarin to initiate the ring-opening polymerization of cyclic esters to synthesize a series of fluorescent biodegradable aliphatic polyesters with tailorable properties. The resulting fluorescent functionalized poly(l-lactide) (PLLA-COU), poly(ε-caprolactone) (PCL-COU) poly(δ-valerolactone) (PVL-COU) and poly(trimethylene carbonate) (PTMC-COU) were investigated to evaluate the dependence of fluorescence on the chemical structure and molecular weight of the materials. The differences in the electron withdrawing ability and the density of ester groups are responsible for the changes in the fluorescence quantum yield.

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Tea-oil camellia () is grown for tea seed oil production, with tea seed cake produced as a byproduct. Rather than disposing of the cake, agricultural uses increase the value of oil production. Constituents of are also utilized for traditional Chinese medicine, as are compounds produced by tree peony roots.

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pH/redox sensitive, dual drug loaded nanoparticles were prepared from poly(ethylene glycol)--poly(l-lysine) (PEG--PLL) for improving cancer therapy. Platinum(iv) and -aconitic anhydride-doxorubicin (CAD) were anchored to lysine residual amine groups of PLL to form polymer prodrug conjugates, which then self-assembled into nanoparticles with hydrophobic platinum(iv) prodrugs and CAD as the core. The nanoparticles were stable in neutral environments, but once under acidic and reductive conditions, the drugs were rapidly released.

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Phosphonic chelating fiber (PCCSF) as a novel adsorbent was produced through alkalization, etherification, amination and phosphonation, and then it was applied to adsorb sulfonamides (SAs), such as sulfadiazine (SD), sulfamonomethoxine (SMM) and sulfamethoxazole (SMZ). Specially, their adsorption behavior at different pH values was studied. As a result, PCCSF was provided with amino (NH or NH) and PO(OH) (PO) groups, and its equilibrium data were generally represented by both Langmuir and Freundlich models.

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In order to lower the capital and operational cost of desalination and wastewater treatment processes, nanofiltration (NF) membranes need to have a high water permeation and ionic rejection, while also maintaining a stable performance through antifouling resistance. Recently, Turing-type reaction conditions [ Science 2018, 360, 518-521] and sacrificed metal organic frame (MOF) nanoparticles [ Nat. Commun.

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Sulfur-chelating based cellulose was produced successfully through alkali-pretreatment, etherification-substitution, amination-crosslinking and sulfurate-reaction. Further, its physico-chemical properties were characterized thoroughly, and several impact factors, i.e.

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