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Environmental context As a low-cost adsorption material with good biocompatibility and high adsorption efficiency, biochar is widely used to treat contaminants in water and soil environments. However, due to its low adsorption capacity and narrow adsorption range, it is necessary to modify biochar to improve its adsorption performance. This review describes the three major biochar modification methods and reviews their adsorption effects on different contaminants, then makes recommendations and suggestions for future development of biochar. Abstract As an adsorption material with low cost, good biocompatibility and high adsorption efficiency, biochar is widely used to treat contaminants in water. By modifying biochar, its physiochemical properties can be effectively improved, thereby improving its directional adsorption capacity for target contaminants. Many studies have been conducted to improve the adsorption capacity of modified biochar for contaminants and to explore the adsorption mechanism. However, there is currently no systematic analysis and summary of various modification methods and their adsorption effects on different contaminants. This review combines all recent papers on the adsorption of contaminants by modified biochar. In addition, this review summarises and specifically divides biochar modification methods into physical modification, chemical modification and compound modification. Physical modification can mainly improve the specific surface area and other physical characteristics of biochar, while chemical modification can form more functional groups in biochar. Compound modification can effectively combine the advantages of different types of adsorption materials to improve the adsorption capacity for contaminants. The adsorption effects of these three types of modification methods on heavy metals, inorganic salts and organic pollutants were compared, and their adsorption mechanisms were systematically reviewed for different types of contaminants. Finally, recommendations and suggestions are put forward for the future development of biochar. In summary, biochar has broad application prospects as a popular adsorption material for the adsorption and removal of contaminants. According to different types of contaminants, a specific modification method can be selected for biochar to achieve the best effect of removing target contaminants.

Highly dispersed silicotungstic acid-derived WO3 composited with ZrO2 supported on SBA-15 (WZ/SBA-15) as an ordered mesoporous solid acid catalyst was prepared via a facile incipient wetness impregnation (IWI) method that active ingredients, ZrO2 and WO3, were impregnated into the channels of SBA-15 simultaneously with a subsequent calcination process. The relationship between catalyst nature and performance was explored by high resolution transmission electron microscopy (HRTEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), FT-IR, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), N2 adsorption-desorption, NH3 temperature-programmed desorption (NH3-TPD), and FT-IR of pyridine adsorption (Py-IR) characterization techniques. The catalytic performance of W12Z15/SBA-15 is not only greater than that of single component solid acid catalysts, WO3/SBA-15 and ZrO2/SBA-15, but also W12/Z15/SBA-15 prepared by impregnating active ingredients, ZrO2 and WO3, into SBA-15 in sequence. The outstanding performance of W12Z15/SBA-15 is derived from the strong interaction between ZrO2 and WO3, which results in more acid sites, and relatively high specific surface area, large pore volume, and ordered mesoporous structure of SBA-15. The characterization and reaction results clearly demonstrate that the synergy of ZrO2 and WO3 has a clear boost for the alkenylation. The optimized W12Z15/SBA-15-500 achieves a 99.4% conversion of phenylacetylene and a 92.3% selectivity of main product α-arylstyrene for the alkenylation of p-xylene with phenylacetylene, with very low level of oligomers producing at the same time. Moreover, W12Z15/SBA-15-500 shows excellent catalytic stability and regeneration. Therefore, W12Z15/SBA-15-500 is a promising solid acid catalyst for the alkenylation.

In this paper, resonance and bifurcation of a nonlinear damped fractional-order Duffing system are studied. The amplitude and phase of the steady-state response of system are obtained by means of average method, and then the amplitude-frequency characteristic curves of the system under different parameters are drawn based on the implicit function equation of amplitude. Grunwald-Letnikov fractional derivative is used to discretize the system numerically, and the response curve and phase trajectory of the system under different parameters are obtained, and the dynamic behavior is analyzed. The forked bifurcation behavior and saddle bifurcation behavior of the system under different parameters are investigated by numerical simulation.

Capacitive deionization (CDI) technology has been considered a promising desalination technique, especially for brackish water, because of its relatively low energy consumption, facile operation, and easy regeneration of electrodes. However, the desalination capacity, cost, fabrication method, electrochemical stability, and environmental unfriendliness of the electrodes have restricted the practical application of the CDI technique. Herein, we reported the one-step in situ preparation of nitrogen-doped and carbon-decorated MXene-derived TiO2 (termed N-TiO2−x/C) through the confinement-growth strategy. The small particle size (∼ 25 nm) and uniform distribution of a peanut-like N-TiO2−x/C material could be ascribed to the confined growth space created by the nanoporous structure of melamine foam. The defects produced by N doping provide an enhanced electrical conductivity and more adsorption sites, while wrapping with a carbon shell layer increases the conductivity and offers protection for N-TiO2−x to achieve an excellent electrochemical stability. The prepared N-TiO2−x/C electrode is hydrophilic due to the abundant oxygen-containing functional groups (e.g., C-O, N-Ti-O, -NOx, and -OH) and exhibits a high salt removal capacity (33.4 mg·g−1), desalination rate (1.5 mg·g−1·min−1), and remarkable cycling stability (without declining after 100 cycles), which might be ascribed to the synergistic effects of the short ion diffusion path, more active adsorption sites, enhanced conductivity, pseudocapacitive behavior, and protection of the carbon shell layer. This work provides a confined-growth strategy to develop MXene-derived oxide electrodes for electrochemical desalination.

Gold nanoclusters (NCs) have received wide attention in basic physical chemistry as well as biomedical applications due to unique electronic structure and luminescence properties. However, expensive cost of gold and weak luminescence prevent their wide applications in biomedicine. Herein, bimetallic fluorescent CuAu NCs were successfully prepared, and the structural, optical properties as well as bioimaging of the CuAu NCs were investigated in detail. The CuAu NCs show the luminescence enhancement compared with Au NCs. Meanwhile, the excellent stability and photostability are also revealed by photoluminescence spectra. The structural investigations reveal that the CuAu NCs are complex clusters with molecule weight of 4.8–5.8 kDa. In addition, the CuAu NCs possess the long fluorescence lifetime of 6.55 μs, which could be associated with metal-centered triplet emission within the clusters. It is also demonstrated that the ultrastable CuAu NCs exhibit low cytotoxicity and can be used for cellular imaging.

Two-dimensional WS

As the abuse of antibiotics has led to increasingly serious environmental pollution problems, studies have found that the adsorption method can be used to efficiently and quickly remove residual antibiotics in water with low cost and high efficiency. Metal-organic frameworks and their derived porous carbons have received widespread attention as a new type of adsorption material. In this study, HKUST-1 was synthesized by a hydrothermal method and carbonized to HDC-350 at 350 °C under an oxygen-free atmosphere. Through adsorption experiments, HDC-350 is found to show a superior adsorption effect for tetracycline (TC), with an adsorption capacity that reaches 136.88 mg g−1. The TC adsorption mechanism was studied through characterization and analysis of HDC-350. The adsorption of TC by HDC-350 mainly relies on electrostatic attraction, hydrogen bonding, metal-organic complexation, and intermolecular interactions. This study shows that HKUST-1-derived porous carbon can be used to improve the water stability of HKUST-1, and, at the same time, can effectively adsorb TC in solution, which provides good conditions for practical research applications in the future.

Gold nanoclusters (NCs) have been widely used in bioimaging and cancer therapy due to their unique electronic structures and tunable luminescence. However, their weak fluorescence prevents potential biomedical application, and thus it is necessary to develop an effective route to enhance the fluorescence of gold NCs. In this work, we report the fluorescence enhancement of ultrasmall GSH-protected Au NCs by Zn atom doping. The fluorescence signal of Zn-doped Au NCs shows approximately 5-fold enhancement compared to pure Au NCs. Density functional theory (DFT) calculation shows that Zn doping can enhance the electronic states of the highest occupied molecular orbital (HOMO), leading to enhancement of visible optical transitions. In vitro experiments show that AuZn alloy NCs can enhance the cancer radiotherapy via producing reactive oxygen species (ROS) and don't cause significant cytotoxicity. In vivo imaging indicates AuZn alloy NCs have significant passive targeting capability with high tumor uptake. Moreover, nearly 80% of GSH-protected AuZn alloy NCs can be rapidly eliminated via urine excretion.

Black phosphorus (BP), as an emerging successor to layered two-dimensional materials, has attracted extensive interest in cancer therapy. Toxicological studies on BP are of great importance for potential biomedical applications, yet not systemically explored. Herein, toxicity and oxidative stress of BP quantum dots (BPQDs) at cellular, tissue, and whole-body levels are evaluated by performing the systemic in vivo and in vitro experiments. In vitro investigations show that BPQDs at high concentration (200 μg/mL) exhibit significant apoptotic effects on HeLa cells. In vivo investigations indicate that oxidative stress, including lipid peroxidation, reduction of catalase activity, DNA breaks, and bone marrow nucleated cells (BMNC) damage, can be induced by BPQDs transiently but recovered gradually to healthy levels. No apparent pathological damages are observed in all organs, especially in the spleen and kidneys, during the 30-day period. This work clearly shows that BPQDs can cause acute toxicities by oxidative stress responses, but the inflammatory reactions can be recovered gradually with time for up to 30 days. Thus, BPQDs do not give rise to long-term appreciable toxicological responses.

Two-dimensional WS2 materials have attracted wide attention in condensed physics and materials science due to its unique geometric and electronic structures. Particularly, WS2 shows extraordinary catalytic activities when its size decreases to ultrasmall, which provides potential opportunities for medical applications. In this work, WS2 quantum dots with strong catalytic properties were used for in vitro and in vivo protection from ionizing radiation induced cell damages. WS2 quantum dots possess unique optical properties of blue photoluminescence emission and excitation-wavelength dependent emission profiles. In vitro studies showed that cell viability can be considerably improved and cellular reactive oxygen species (ROS) can be removed by WS2 quantum dots. In vivo studies showed WS2 quantum dots can effectively protect the hematopoietic system and DNA from damages caused by high-energy radiation through removing whole-body excessive ROS. Furthermore, WS2 quantum dots showed nearly 80% renal clearance w...

Background and Purpose Liver diseases are mostly accompanied by inflammation and hepatocyte death. Therapeutic approaches targeting both hepatocyte injury and inflammation are not available. Natural compounds are considered as potential treatment for inflammatory liver diseases. Hesperetin, a flavonoid component of citrus fruits has been reported to have anti-inflammatory properties. The aim of this study was to evaluate the cytoprotective and anti-inflammatory properties of hesperetin both in vitro and in models of fulminant hepatitis. Experimental Approach Apoptotic cell death and inflammation were induced in primary cultures of rat hepatocytes by bile acids and cytokine mixture, respectively. Apoptosis was quantified by caspase-3 activity and necrosis by LDH release. The concanavalin A (ConA) and D-galactosamine/LPS (D-GalN/LPS) were used as models of fulminant hepatitis. Liver injury was assessed by ALT and AST levels, liver histology and TUNEL assay and inflammation by inducible Nitric Oxide Synthase (iNOS) expression. Key Results Hesperetin blocked bile acid-induced apoptosis and cytokine-induced inflammation in rat hepatocytes. Moreover, hesperetin improved liver histology and protected against hepatocyte injury in ConA- and D-GalN / LPS-induced fulminant hepatitis, as assessed by TUNEL assay and serum AST and ALT levels. Hesperetin also reduced expression of the inflammatory marker iNOS and the expression and serum levels of TNFα and IFN-γ, the main mediators of cell toxicity in fulminant hepatitis. Conclusion and Implications Hesperetin has anti-inflammatory and cytoprotective actions in models of acute liver toxicity. Hesperetin therefore has therapeutic potential for the treatment of inflammatory liver diseases accompanied by extensive hepatocyte injury, such as fulminant hepatitis.

Reduced graphene oxide&ndash, titanium dioxide photocatalyst (rGO&ndash, TiO2) was successfully synthesized by the hydrothermal method. The rGO&ndash, TiO2 was used as photocatalyst for the degradation of bisphenol A (BPA), which is a typical endocrine disruptor of the environment. Characterization of photocatalysts and photocatalytic experiments under different conditions were performed for studying the structure and properties of photocatalysts. The characterization results showed that part of the anatase type TiO2 was converted into rutile type TiO2 after hydrothermal treatment and 1% rGO&ndash, P25 had the largest specific surface area (52.174 m2/g). Photocatalytic experiments indicated that 1% rGO&ndash, P25 had the best catalytic effect, and the most suitable concentration was 0.5 g/L. When the solution pH was 5.98, the catalyst was the most active. Under visible light, the three photocatalytic mechanisms were ranked as follows: O2&bull, &minus, &gt, &bull, OH &gt, h+. 1% rGO&ndash, P25 also had strong photocatalytic activity in the photocatalytic degradation of BPA under sunlight irradiation. 1% rGO&ndash, P25 with 0.5 g/L may be a very promising photocatalyst with a variety of light sources, especially under sunlight for practical applications.

In recent years, metal–organic framework materials (MOFs) have been widely used in adsorption, separation, storage, and transportation due to their advantages of adjustable composition, diverse structures, and controllable pore size. MOF-derived porous carbon materials inherit the advantages of MOFs of the large surface area, high porosity, and customizability, that can be applied to the adsorption of the pollutants in the environment. In this study, we review the preparation methods commonly used to synthesize MOFs-derived porous carbon adsorbents in recent years, as well as the research progress on the adsorption of organic and inorganic pollutants in the liquid phase, and discuss the factors affecting the adsorption property of MOF-derived carbon. Finally, the challenges and development prospects of MOFs-derived porous carbon in the field of adsorption are discussed.

Plastic debris becomes currently a ubiquitous environmental pollutant and is susceptible to contamination by many other pollutants, including aqueous metals and organic matter. This review summarizes the effects of environmental factors on the properties and sorption behavior of microplastics, presents a further discussion on the fate of microplastics adsorption on contaminants, and critically discusses the mechanism of sorption behaviors between micro/nanoplastics and normal contaminants. Previous references indicated that the hydrophobicity and particle sizes of microplastics were the dominant influence factors for virgin plastic debris adsorption, whereas for aged microplastics, hydrogen bonding, hydrophilicity and increasing specific surface ratio affected the adsorption behavior. The effects of pH and salinity always influence the sorption conditions by changing the charge state of microplastics and contaminants and causing competing adsorption. In addition, the existence of microplastics affects biotoxicity, increases the dissolved organic matter in the environment, and influences carbon cycling. The knowledge is fundamental to the assessment of potential risks posed by microplastics to organisms from human beings to the entire environment.

Gold nanoclusters (NCs) have been widely used in bioimaging and cancer therapy due to their unique electronic structures and tunable luminescence. However, their weak fluorescence prevents potential biomedical application, and thus it is necessary to develop an effective route to enhance the fluorescence of gold NCs. In this work, we report the fluorescence enhancement of ultrasmall GSH-protected Au NCs by Zn atom doping. The fluorescence signal of Zn-doped Au NCs shows approximately 5-fold enhancement compared to pure Au NCs. Density functional theory (DFT) calculation shows that Zn doping can enhance the electronic states of the highest occupied molecular orbital (HOMO), leading to enhancement of visible optical transitions.

In this paper, a kind of modified GMRES(m) algorithm is proposed and its convergence theory is well established. By properly varying the restart parameter m in the GMRES(m) algorithm, the computational efficiency and precision can be significantly improved. Because the parameter m can be very small, the storage and computations are greatly saved. In addition, the new algorithm is successfully used to solve a heat conduction problem and a Laplace equation problem. Numerical results show that it is not only highly effective and accurate, but also can avoid slow convergence or failure behaviour of the GMRES(m) algorithm. The superiorities will be much more remarkable for the solution of large scale problems. So it has extensive prospect in scientific computing and engineering applications.

Liver diseases are mostly accompanied by inflammation and hepatocyte death. Therapeutic approaches targeting both hepatocyte injury and inflammation are not available. Natural compounds are considered as potential treatment for inflammatory liver diseases. Hesperetin, a flavonoid component of citrus fruits, has been reported to have anti-inflammatory properties. The aim of this study was to evaluate the cytoprotective and anti-inflammatory properties of hesperetin both in vitro and in models of fulminant hepatitis.Apoptotic cell death and inflammation were induced in primary cultures of rat hepatocytes by bile acids and cytokine mixture respectively. Apoptosis was quantified by caspase-3 activity and necrosis by LDH release. The concanavalin A (ConA) and D-galactosamine/LPS (D-GalN/LPS) were used as models of fulminant hepatitis. Liver injury was assessed by alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, liver histology and TUNEL assay and inflammation by inducible NOS (iNOS) expression.Hesperetin blocked bile acid-induced apoptosis and cytokine-induced inflammation in rat hepatocytes. Moreover, hesperetin improved liver histology and protected against hepatocyte injury in ConA- and D-GalN/LPS-induced fulminant hepatitis, as assessed by TUNEL assay and serum AST and ALT levels. Hesperetin also reduced expression of the inflammatory marker iNOS and the expression and serum levels of TNFα and IFN-γ, the main mediators of cell toxicity in fulminant hepatitis.Hesperetin has anti-inflammatory and cytoprotective actions in models of acute liver toxicity. Hesperetin therefore has therapeutic potential for the treatment of inflammatory liver diseases accompanied by extensive hepatocyte injury, such as fulminant hepatitis.

Short-term exposure to cigarette smoke (CS) introduces an abundance of free radicals into the lungs, causing oxidative stress and inflammation. CS is an important risk factor related to the pathogenesis of several pulmonary diseases, especially chronic obstructive pulmonary disease. Black coral (BC) is a marine biomaterial commonly used for cigarette holders in southeast China. The purpose of the present study was to evaluate the in vivo bioactivity of BC extract (BCE). Groups of mice (male Kunming) were subjected to ultrasonic atomizing inhalation of BCE (0.3, 1.5, and 3 mg/mL) before being exposed to CS (10 cigarettes per day for 4 days). The control group and the CS group were administered normal saline rather than BCE prior to CS exposure. Superoxide dismutase (SOD), malondialdehyde (MDA), and myeloperoxidase (MPO) levels were measured in lung homogenates. Histologic and morphologic studies of the right upper lung were performed. SOD activity increased 1.32 times in the CS+BCE (3 mg/mL) group (P.001) compared with the CS group. The MDA content increased 4% (P.001) in the CS+BCE (3 mg/mL) group compared with the control group. MPO was reduced 40% in the CS+BCE (3 mg/mL) group compared with the CS group (P.001). Histologic analysis revealed decreased inflammation in the BCE group compared with the CS group. These results suggest that BCE has antioxidant and anti-inflammatory activity in vivo. BCE may protect against lung injury in smokers.

High-energy ionizing radiation is widely used in medical diagnosis and cancer radiation therapy. However, high-energy radiation can also impose significant damages in healthy tissues during medical treatments via direct DNA damages and indirect damages from production of reactive oxygen species (ROS). Therefore, it is urgent to develop highly effective radioprotectants with low toxicities that can meet the increasing needs for alleviating the adverse effects from cancer radiation therapy and nuclear emergency. In this work, strongly catalytic ultrasmall (sub-5 nm) cysteine-protected WSe2 dots are employed to protect healthy tissues against radiation via diminishing radiation-induced free radicals. The WSe2 dots with high surface activities can recover radiation-induced DNA damages and eliminate the excessive ROS generated from radiation. In vivo experiments confirm that the survival rate of mice treated with WSe2 dots is significantly elevated with radiation damages postponed under exposure to high-dose ionizing radiation. Furthermore, the free radicals in major organs and hematological system can be appreciably omitted, suggesting their unique role as free radical scavengers. These WSe2 dots in ultrasmall size show rapid renal clearance of ≈74% injection dose via urine excretion in 24 h and do not cause any apparent toxicity in vivo for up to 30 d.

To solve large scale linear equations involved in the Fast Multipole Boundary Element Method (FM-BEM) efficiently, an iterative method named the generalized minimal residual method (GMRES(m)) algorithm with Variable Restart Parameter (VRP-GMRES(m)) algorithm is proposed. By properly changing a variable restart parameter for the GMRES(m) algorithm, the iteration stagnation problem resulting from improper selection of the parameter is resolved efficiently. Based on the framework of the VRP-GMRES(m) algorithm and the relevant properties of generalized inverse matrix, the projection of the error vector r m + 1 on r m is deduced. The result proves that the proposed algorithm is not only rapidly convergent but also highly accurate. Numerical experiments further show that the new algorithm can significantly improve the computational efficiency and accuracy. Its superiorities will be much more remarkable when it is used to solve larger scale problems. Therefore, it has extensive prospects in the FM-BEM field and other scientific and engineering computing.

Ipomoea stolonifera (I. stolonifera) has been used for the treatment of inflammatory diseases including rheumatism and rheumatoid arthritis in Chinese traditional medicine. However, the anti-inflammatory activity of I. stolonifera has not been elucidated. For this reason, the anti-inflammatory activity of n-butanol extract of I. stolonifera (BE-IS) was evaluated in vivo by using acute models (croton oil-induced mouse ear edema, carrageenan-induced rat paw edema, and carrageenan-induced rat pleurisy) and chronic models (cotton pellet-induced rat granuloma, and complete Freund’s adjuvant (CFA)-induced rat arthritis). Results indicated that oral administration of BE-IS significantly attenuated croton oil-induced ear edema, decreased carrageenan-induced paw edema, reduced carrageenan-induced exudates and cellular migration, inhibited cotton pellet-induced granuloma formation and improved CFA-induced arthritis. Preliminary mechanism studies demonstrated that BE-IS decreased the levels of myeloperoxidase (MPO) and malondialdehyde (MDA), increased the activity of anti-oxidant enzyme superoxide dismutase (SOD) in vivo, and reduced the production of nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6 in lipopolysaccharide-activated RAW264.7 macrophages in vitro. Results obtained in vivo and in vitro demonstrate that BE-IS has considerable anti-inflammatory potential, which provided experimental evidences for the traditional application of Ipomoea stolonifera in inflammatory diseases.

Black corals (BC) have been used for a long time in Chinese medicine, and may have some pharmaceutical functions when used as material for cigarette holders in southeast China. This study is aimed to investigate the bioactivities of volatile constituents in BC and to explore the folklore behind the use of BC cigarette holders (BCCHs). We extracted the volatile constituents of BC by supercritical fluid extraction (SFE) with carbon dioxide (CO2-SFE), then identified and analyzed the constituents by gas chromatography-mass spectrometry (GC-MS). In total, 15 components were reliably identified in BC and found to be biologically active. These included triethyl phosphate, butylated hydroxytoluene, cedrol, n-hexadecanoic acid, squalene, and cholesterol. Meanwhile 13 inorganic elements (P, Ca, Mg, S, B, Si, Fe, Cu, Zn, Ba, etc.) were determined by inductively coupled plasma spectrometer (ICPS). In the bioactivity tests, the BC extract (BCE) showed a scavenging activity of 2,2-diphenyl-1-picrylhydrazyl free radicals and hydroxyl radicals by phenanthroline-Fe (II) oxidation and moderate inhibition of Gram-positive microorganisms. The antioxidant and antimicrobial activities of BC, which are related to the active chemical composition, may explain the perceived benefit for cigarette smokers who use BCCHs.