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This work focused on the separation of the active ingredients of maca (Lepidium meyenii Walpers) and evaluated the antioxidative capability of these components with effects on improving glucose and lipid metabolism in insulin‐resistant HepG2 cells. DPPH free radical scavenging and reducing power assays were used to evaluate the antioxidant activity of maca extracts. An insulin‐resistant HepG2 cell model induced by glucose, fructose, oleic acid, and palmitic acid was adopted to investigate the effects of maca extracts on regulating glucose and lipid metabolism in this study. LC‐MS/MS was then used for determination of the maca n‐butanol (NBT) subfraction. The results showed that maca ethanol extract and subfractions of this extract exhibited certain antioxidant capacity. Furthermore, the NBT subfraction reversed the disorders in glucose and lipid metabolism in insulin‐resistant HepG2 cells and significantly increased the mRNA expression of phosphoinositide 3‐kinases (PI3K) and AKT in insulin‐resistant HepG2 cells in a dose‐dependent manner. In addition, the LC‐MS/MS results showed that the NBT subfraction contained many active ingredients. Overall, this study suggests that the NBT subfraction of the ethanol extract rich in glucosinolates modulates insulin resistance via PI3K/AKT activation in insulin‐resistant HepG2 cells and might exert potentially beneficial effects in improving or treating glucose and lipid metabolic disorders., This work focused on the separation of Maca (Lepidium meyenii Walp.) active ingredients, and evaluated the antioxidative capability of these components with the effects on improving glucose and lipid metabolism in insulin resistant HepG2 cells.

Landfill leachate was gasified in supercritical water (SCW) in a batch reactor made of 316 SS. The effects of temperature, pressure, reaction time and oxidation coefficient (OC) on the pollutant removal efficiencies and gasification characteristics were investigated. To observe the formation of tar and char visually, a capillary quartz reactor was also used. Results indicated that CO2, H2 and CH4 were the most abundant gaseous products. Temperature has an appreciable effect on the gasification process. Increasing temperature enhanced the H2 yield (GYH2) and TOC removal efficiency (TRE) significantly. Although the influence of reaction time on the fractions of gaseous products was negligible at time above 300 s, the yields of H2, CH4, and CO2 increased with reaction time whereas the CO, C2H4 and C2H6 yields decreased. Tar and char formation was evident on the interior surface of capillary quartz reactor. Adding a little oxidant could increase H2 and CH4 yields and decrease tar and char formation. GYH2 reached up to the maximum of 231.3 mmol L−1 leachate at 500 °C, 25 MPa, 600 s and 0.2 OC, which was 2.4 times of that without oxidant.

Natural organic matter (NOM) is present in source water worldwide, and it is composed of numerous organic compounds produced in natural processes. NOM has been drawing increasing concerns because it not only affects drinking water treatment on many aspects (e.g., the performance of treatment techniques, necessity of advanced treatment, the dose of treatment chemicals, etc.), but also acts as the main precursor of hazardous drinking water disinfection byproducts (DBPs). Accordingly, to optimize treatment processes and to control the formation of DBPs, it is vital to analyze and characterize NOM for a better understanding of its property and reactivity. In this review, a summary of methods used in NOM analysis and characterization during drinking water treatment was provided, including analysis methods for general parameters (e.g., dissolved organic carbon, dissolved organic nitrogen, (specific) ultraviolet absorbance, fluorescence, polarity, and zeta potential) and characterization methods for elemental and structural identification (e.g., elemental analysis, Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, pyrolysis-gas chromatography/mass spectrometry, liquid chromatography/mass spectrometry, and Fourier transform ion cyclotron resonance mass spectrometry). In addition, preparation and pretreatment methods for NOM were also covered in this review, including isolation and concentration methods (reverse osmosis, pressure-reducing evaporation, freeze-drying, and electrodialysis) as well as fractionation methods (size exclusion chromatography, resin fractionation, membrane filtration, polarity rapid assessment, field-flow fractionation, and reversed-phase high performance liquid chromatography).

Arrowhead (Sagittaria trifolia var. sinensis) is a source of starch worldwide, but arrowhead starch has been rarely studied. In this work, starch was separated from arrowhead corm. The morphology and physicochemical properties of starch were then investigated and compared among 3 different arrowhead varieties (Purple-corm, Hongta, and Japanese). Results showed that starches from the 3 varieties similarly featured an oval shape containing a visible polarization cross, a CA -type crystalline structure, and an ordered structure in the external granule region. However, starch content, granule size, crystal characteristics, and pasting properties differed among the 3 varieties. Japanese arrowhead exhibited the highest starch content and degree of ordered structure in the external granule region, as well as onset, peak, and final gelatinization temperature. Purple-corm arrowhead starch demonstrated the highest amylose content and relative degree of crystallinity, smallest granule size, and lowest swelling power and solubility. Purple-corm arrowhead starch also showed the highest gelatinization enthalpy, as well as peak, trough, final, and setback viscosities. This starch further presented the lowest breakdown viscosity and degree of hydrolysis by HCl and porcine pancreatic α-amylase. These findings can provide useful references for arrowhead variety selection in food and nonfood industries.

Lilium (Liliaceae) is an important wild plant and is used as food and traditional medicine worldwide. One Lilium cultivar (Lilium lancifolium) and 2 wild types (Lilium leucanthum and Lilium rosthornii) that are commonly distributed in Western China were investigated to completely utilize Lilium resources. The morphology of the flowers, bulbs, and scales and soluble sugar, total starch and amylose contents was remarkably different among the 3 Lilium species. Starches from the 3 Lilium species presented different granule size and shape. The starch of L. lancifolium exhibited higher swelling power and solubility than that of L. leucanthum and L. rosthornii. The starches from the 3 Lilium bulbs presented similar X-ray diffraction patterns and Fourier transform infrared spectroscopy. Among the 3 Lilium species, L. lancifolium showed the lowest crystallinity and the largest proportion of ordered structures in granule external region. Gelatinization temperatures and retrogradation percentage were significantly lower, but gelatinization enthalpy was significantly higher in L. lancifolium than those in L. leucanthum and L. rosthornii. Pasting properties of starch were different among the 3 Lilium species. Starch from L. lancifolium showed the highest degree of amylopectin branching, followed by L. leucanthum and L. rosthornii. Starches from L. leucanthum and L. rosthornii showed higher resistance to porcine pancreatic α-amylase hydrolysis compared to that of L. lancifolium. These results indicated that 3 Lilium bulbs exhibited remarkable differences in morphological, crystal, thermal, pasting, and hydrolysis properties of starches.

In this work, the continuous pyrolysis of pine sawdust is performed with a screw reactor to investigate the influence of pyrolysis temperature and solid residence time on products and energy distribution. Gas chromatograph/mass spectrometer (GC/MS) and Fourier transform infrared spectroscopy (FTIR) were used to confirm the identities of bio-oil. The combustion kinetics of bio-char had analyzed by thermo-gravimetric (TG). The results of gas chromatograph showed that carbon monoxide is the main component in produced gas, and the maximum gas yield of 54.5% was obtained at the temperature of 900 °C. Compositional analysis of the oil products showed that phenols were the major components, and its proportion increased at higher temperatures and longer solid residence times. The activation energy of bio-char combustion is 461.10 kJ mol−1 and 108.45 kJ mol−1 in the ranges of 290–314 °C and 314–518 °C, respectively. The maximum of energy profit rate is 6.49% obtained at the temperature of 900 °C with the solid residence time of 6 min.

A rapid and effective method based on a novel permanent magnetic hypercrosslinked resin W150 was proposed for the removal of organic micropollutants in drinking water. W150 was prepared by suspension and post-crosslinking reaction and found to possess a high specific surface area of 1149.7 m2·g−1, a small particle size of 50 μm to 100 μm, and a saturation magnetization as high as 8 emu·g−1. W150 was used to eliminate nitrofurazone (NFZ) and oxytetracycline (OTC) from drinking water compared with commercial adsorbents XAD-4 and F400D. The adsorption kinetics of NFZ and OTC onto the three adsorbents well fitted the pseudo-second-order equation (r>0.972), and the adsorption isotherms were all well described by the Freundlich equation (r>0.851). Results showed that the reduction in adsorbent size and the enlargement in sorbent pores both accelerated adsorption. Moreover, the effect of particle size on adsorption was more significant than that of pore width. Given that the smallest particle size and the highest specific surface area were possessed by W150, it had the fastest adsorption kinetics and largest adsorption capacity for NFZ (180 mg·g−1) and OTC (200 mg·g−1). For the adsorbents with dominant micropores, the sorption of large-sized adsorbates decreased because of the inaccessible micropores. The solution pH and ionic strength also influenced adsorption.

The occurrence rates of non-communicable diseases like obesity, diabetes and hyperlipidemia have increased remarkably due to excessive consumption of a high-energy diet. Rare sugars therefore have become increasingly attractive owing to their unique nutritional properties. In the past two decades, various rare sugars have been successfully prepared guided by the “Izumoring strategy”. As a valuable complement to the Izumoring approach, the controllable dihydroxyacetone phosphate (DHAP)-dependent aldolases have generally predictable regio- and stereoselectivity, which makes them powerful tools in C-C bond construction and rare sugar production. However, the main disadvantage for this group of aldolases is their strict substrate specificity toward the donor molecule DHAP, a very expensive and relatively unstable compound. Among the current methods involving DHAP, the one that couples DHAP production from inexpensive starting materials (for instance, glycerol, DL-glycerol 3-phosphate, dihydroxyacetone, and glucose) with aldol condensation appears to be the most promising. This review thus focuses on recent advances in the application of L-rhamnulose-1-phosphate aldolase (RhaD), L-fuculose-1-phosphate aldolase (FucA), and D-fructose-1,6-bisphosphate aldolase (FruA) for rare sugar synthesis in vitro and in vivo, while illustrating strategies for supplying DHAP in efficient and economical ways.

A novel hyper-crosslinked resin (MENQ) modified with an anion exchange group was prepared using divinylbenzene (DVB) and methyl acrylate (MA) as comonomers via four steps: suspension polymerization, post-crosslinking, ammonolysis and alkylation reactions. The obtained resin had both a high specific surface area (793.34 m2·g−1) and a large exchange capacity (strong base anion exchange capacity, SEC: 0.74 mmol·g−1, weak base anion exchange capacity, WEC: 0.45 mmol·g−1). XAD-4 was selected as an adsorbent for comparison to investigate the adsorption behavior of tetracycline (TC) and humic acid (HA) onto the adsorbents. The results revealed that MENQ could effectively remove both TC and HA. The adsorption capacity of XAD-4 for TC was similar to that of MENQ, but XAD-4 exhibited poor performance for the adsorption of HA. The adsorption isotherms of TC and HA were well-fitted with the Freundlich model, which indicated the existence of heterogeneous adsorption through cation-π bonding and π-π interactions. The optimal solution condition for the adsorption of TC was at a pH of 5–6, whereas the adsorption of HA was enhanced with increasing pH of the solution.

The adsorption of phenol, p-nitrophenol, aniline, and nitrobenzene onto a commercial granular activated carbon (GAC: F400) preloaded with tannic acid (TA), a model background contaminant, was investigated. Compared with virgin GAC, the adsorption capacities of the four selected aromatic organic compounds (AOCs) onto GACs preloaded with TA at three densities were affected significantly. Also, the relationship between the adsorption capacities of AOCs and the characteristics of GACs was further discussed and clarified in this manuscript. The differences in the functional groups attached to the AOCs did not affect the similar linear relationship between the micropore surface area and their capacities to AOCs. However, the adsorption capacities of AOCs on TA-loaded GAC were affected by the different functional groups on the four AOCs: 67.6% of the capacity of aniline for virgin F400 remained on F400c (a preloaded GAC), compared with 23.8, 25.9, and 36.5% of phenol, p-nitrophenol, and nitrobenzene, respectively. The diversity of adsorption behavior of the four AOCs with different substituents was the result of hybrid contributions, such as hydrogen bonding, hydrophobic effect and aromatic stacking.

Dissolved organic matter (DOM) is a typical kind of pollutant with a complex composition, and different advanced treatments demonstrate different abilities toward its fractional removal. Hence, it is necessary to analyze the fraction of DOM that remains when using advanced treatments. In this paper, ozonation was used to deal with the biological effluents and comparisons of the catalytic ozonation with different particle sizes of &gamma, Al2O3 were made. The results of these comparisons indicated that the catalysts were active in improving the removal of DOM and &gamma, Al2O3 with different particle sizes can selectively remove DOM. The result of fluorescence showed that a decrease in the catalyst particle size contributes to a significant decrease in the fluorescence intensity, except for tryptophan-like substances. Meanwhile, DOM fractions with large molecular weights could be decomposed into small molecules by ozonation, resulting in increased hydrophilicity. However, the use of a catalyst in ozonation increased the removal of hydrophilic components. Additionally, a smaller catalyst particle size increased the removal of hydrophilic components. The results of catalyst analysis implied that the surface hydroxyl groups of catalyst &gamma, Al2O3 and the diffusion of DOM in the catalyst &gamma, Al2O3 played important roles in the ozonation catalytic process for the removal of DOM.

Both bottle-point and column-feeding experiments involving different solutes and sorbents were carried out to investigate the adsorption selectivity and separation performance of salicylic acid and 5-sulfosalicylic acid. Their adsorption isotherms onto such hypercrosslinked polymeric adsorbents as NDA-100 and NDA-99 could be well described by the Freundlich equations whose characteristics describe extrathermic and favorable adsorption processes. The adsorption towards NDA-100 mainly depended on the π-π interaction, while that towards NDA-99 was extremely influenced by the static-electric interaction. Additionally, the adsorptive capacity of salicylic acid on NDA-99 decreased while it increased on NDA-100 with the presence of 5-sulfosalicylic acid in the adsorptive environment as the competitive component. Comparatively, the adsorption capacity of 5-sulfosalicylic acid decreased on both resins with salicylic acid as the competitive component. In fact, the difference in the interaction between adsorbent and adsorbate resulted in the straight antagonism on the effective adsorption sites on the adsorbent. In conclusion, the adsorption selectivity of salicylic acid onto NDA-100 was obviously larger than that onto NDA-99 with the existence of 5-sulfosalicylic acid in the adsorptive environment. A satisfactory separation and recovery of tested solutes in aqueous phase could be foreseeably achieved by the sequencing adsorption technique involving NDA-100 as well as NDA-99.

In the present study, a hydrophilic bifunctional polymeric resin (LS-2) with sulfonic groups was synthesized, and the adsorption performance of three aniline compounds, aniline, 4-methylaniline, and 4-nitroaniline onto LS-2 was compared with that on the commercial Amberlite XAD-4. The uptake of the aniline compounds on LS-2 is a procedure of coexistence of physisorption and chemisorption and obeys the pseudo-second order rate equation, while the uptake of the compounds on XAD-4 is merely a physical adsorption and follows the pseudo-first order rate equation. All the isothermal data fit well with the Freundlich model, and the values of K(F) of the compounds adsorbing on LS-2 are much higher than those on XAD-4 suggesting the higher adsorbing capacities on LS-2 than those on XAD-4, which may be attributed to the microporous structure and the polar groups on the network of LS-2 resin. Dynamic adsorption and desorption studies for aniline on LS-2 show that the breakthrough adsorption capacity and the total adsorption capacity are 0.96 and 1.24 mmol per milliliter resin, respectively. Nearly 100% regeneration efficiency for the adsorbent was achieved by 5% hydrochloric acid.

In this paper a new bifunctional polymeric resin (LS-2) was synthesized by introducing sulfonic groups onto the surface of the resin during the post-crossing of chloromethyl low crosslinking macroporous poly-styrene resin, and the comparison of the adsorption properties of LS-2 with Amberlite XAD-4 toward aniline and 4-methylaniline in aqueous solutions was made. The study focuses on the static equilibrium adsorption behaviors, the adsorption thermodynamics, and the column dynamic adsorption and desorption profiles. Freundlich model gives a perfect fitting to the isotherm data. Although the specific surface area of LS-2 is lower than that of Amberlite XAD-4, the adsorbing capacities for these two adsorbates on LS-2 are higher than those on Amberlite XAD-4 within the temperature range 288-318 K, which is contributed to microporous structure and the polar groups on the network of LS-2 resins. The adsorption for aniline or 4-methylaniline on LS-2 was proved to be an endothermic process and increasing temperature was favorable. From the studies on the adsorption thermodynamics, static equilibrium adsorption, and the desorption conditions, an important conclusion can be drawn that the adsorption for aniline or 4-methylaniline on the LS-2 is a coexistence process of physical adsorption and chemical transition.

A commercially available polymeric adsorbent NDA-99 and two new synthesized polymeric adsorbents NPA and AMR have been used for the adsorption of reactive dye (reactive brilliant blue XBR, abbreviated as XBR) from aqueous solution. The batch system was applied to study the adsorption equilibrium on the three polymeric adsorbents. Equilibrium adsorption data were obtained and fitted very well to Freundlich model. The results showed that the pore size distribution (PSD) and the amino groups on the polymer played a significant role in XBR adsorption performance, and polymer AMR exhibited the highest adsorption capacities due to the suitable PSD and the presence of amino groups. The free energy changes ΔG for adsorption of reactive dye XBR on the three polymeric adsorbents in the solution at 303 K were evaluated. The negative values of ΔG indicated overall adsorption processes were spontaneous and thermodynamically favorable.

The adsorption of lipoic acid on three different types of resin was compared. Studies of the adsorption thermodynamics and kinetics of lipoic acid onto XAD-4, NDA-100 and ND-90 resins were carried out via static experiments. The results showed that the polar groups and micropore ranges associated with the resins played a significant role in the adsorption of lipoic acid. Such processes were exothermic and involved physical adsorption. The adsorption of lipoic acid onto XAD-4 resin corresponded to the formation of a Langmuir monolayer, with the adsorption velocity appearing to follow first-order kinetics. The adsorption data of lipoic acid onto NDA-100 and ND-90 resins were also well fitted by the Langmuir isotherm, which was associated with capillary condensation and volume filling of micropores besides monolayer adsorption. In contrast, the adsorption of lipoic acid onto NDA-100 and ND-90 resins involved two pore ranges: macropore + mesopore and micropore. The adsorption velocities for the two ranges followed first-order kinetics.

Adsorption of lipoic acid on three different types resin was compared. Study on adsorption thermodynamics and kinetics of lipoic acid by XAD-4, NDA-100 and ND-90 resin was carried out through static experiments. The results show the polar groups and the micropores range on the resin play a significant role on adsorption of lipoic acid. These adsorption processes of lipoic acid are indicative of exothermic process and physical adsorption. The adsorption of lipoic acid on XAD-4 resin is Langmuir monolayer and the adsorption velocity appears to be the first order kinetics. The adsorption data of lipoic acid on NDA-100 and ND-90 resins also fit well to the Langmuir isotherm, which is caused by the capillary condensation and the volume filling of micropores besides monolayer adsorption. The adsorption of lipoic acid on NDA-100 and ND-90 resins passes through two phases: macropores and mesopores range and micropores range. And the adsorption velocities of the two phases are the first order kinetics.

A polyfunctional hypercrosslinked polymeric adsorbent, LA-8, was synthesized and characterized. It was first used to investigate the adsorption properties of 1-amino-2-naphthol-4-sulphonic acid (1,2,4-acid), including the corresponding adsorption isotherms, thermodynamics and binary competitive adsorption with 2-naphthol. The Freundlich model gave good fits to both the single and binary adsorption isotherms, indicating an endothermic and favourable adsorption process. The positive value of ΔH 0 for the single solute system was in the range of 30–60 kJ/mol showing the existence of integrated processes involving chemical interaction. The values of ΔG 0 demonstrated the spontaneous nature of the adsorption process while the value of ΔS 0 showed increased randomness at the solid–solution interface, thereby indicating the presence of stoichiometric displacement. Both ΔH 0 and ΔS 0 appeared to vary linearly with increased solid loading, q e . Pre-adsorbed 2-naphthol molecules supplied another adsorption site for 1,2,4-acid, despite the existence of an antagonistic interaction with 2-naphthol. In simultaneous processes, the mechanism for 1,2,4-acid adsorption probably mainly involved van der Waals forces and hydrogen-bonding interaction. Furthermore, the adsorption of a greater amount of 2-naphthol onto the solid phase demonstrated the occurrence of interaction between the tested binary solutes. It was concluded that direct competition for adsorption sites was the dominant competitive mechanism.

Two hypercrosslinked polymeric adsorbents NG-99 and NG-100 were employed to remove four phenylhydrazine derivatives, phenylhydrazine (PH), 1-methyl-1-phenylhydrazine (1-MPH), 1-acetyl-2-phenylhydrazine (1-APH) and p-methylphenylhydrazine (p-MPH) from aqueous solutions. A comparison of the thermodynamic behaviors against the two hypercrosslinked resins and the conventional macroporous resin Amberlite XAD-4 was made. It was found that the equilibrium adsorption data for the four phenylhydrazine compounds fitted well to the Langmuir isotherms, suggesting a physical and mono-molecular layer adsorption process. The results showed that the equilibrium adsorption capacities of PH, 1-MPH, 1-APH and p-MPH on NG-99 and NG-100 were all higher than that on Amberlite XAD-4 by 20–70%, which may be attributed to the uniform micropore structure and partial polarity on the network of the hypercrosslinked resins, as well as the enhanced π–π interactions and the better compatibility between the adsorbates and adsorbents, and NG-100 demonstrated the highest adsorption capacity. The sorption enthalpies were calculated to interpret the adsorption mechanism. In addition a kinetic study of the sorption of PH onto NG-100 was also carried out. A first-order irreversible reaction rate equation was assumed for the sorption system and was suitable to describe the physisorption process. The hypercrosslinked polymer NG-100 exhibited optimum potential for removing PH derivatives from aqueous solutions.

In the present study a hypercrosslinked macroporous polymer CHA-111 was chemically modified by amination with dimethylamine. Adsorption of five aromatic acids on the modified polymer MCH-111 was investigated and adsorption capacities of aromatic acids from aqueous solution increased significantly after amination. The Freundlich and Langmuir isotherm equations were employed to fit the adsorption processes to describe adsorption mechanism. Hydrogen-bonding interaction should be regarded as a fundamental contributor to increasing adsorption capacities of aromatic acids on MCH-111. Surface structure of MCH-111 caused by postcrosslinking reaction will enhance the NPM–matrix interaction and then lead to higher activity of amino group on MCH-111 than a macroporous weakly anion exchanger D301. The negative isosteric enthalpy changes for adsorption of benzenesulfonic acid and naphthalenesulfonic acid indicate an exothermic process on the aminated polymer.

MBT is a relevant method used as a pretreatment technique for MSW, especially for the MSW with high organic content and high moisture content. As the MBT method can greatly reduce the weight and water content of MSW, the properties and combustion characteristics of original and treated MSW would be very different. The treated MSW has a lower weight and moisture content compared to the original. The total weigh decreases by 30% and the percentage of water decreases by 16%. Meanwhile, percentages of combustible contents increase by 13%. Changes in the concentrations of treated MSW result in a high LHV of 7362 kJ kg-1 while the LHV of original MSW is 2468 kJ kg-1. Larger particles of treated MSW have a much higher volatile matter content, but a lower fixed carbon content and ash content. As for the LHV, it was declined with diameters. TGA is used here to evaluate the effect of MBT on the combustion characteristics of MSW. Results of TGA show that with the exception of one original MSW sample, other samples all have three peaks in their DTG curves with the maximum DTG values approximately occur at290 oC, 440 oC and 650 oC, respectively.

As a kind of biomass resources, the corncob is widely applied in the product of furfural. At present, the yield of furfural has consumed half of the corncob product in China each year. The high pollution and high energy consumption are the choke points which restrict the development of furfural. In this paper, the wastewater and fume was investigated in detail. The major problem was the wastewater couldni¯t be disposed completely and large amount of wastewater was discharged privately. At the same time, high concentration SO2, CO, NO and NOx in fume was discharged directly.

Refractory dissolved organic matter (DOM) from landfill leachate treatment plant was with high dissolved organic carbon (DOC) content. An aminated polymeric adsorbent NDA-8 with tertiary amino groups and sufficient mesopore was synthesized, which exhibited high adsorption capacity to the DOM (raw water after coagulation). Resin NDA-8 performed better in the uptake of the DOM than resin DAX-8 and A100. Electrostatic attraction was considered as the decisive interaction between the adsorbent and adsorbate. Special attention was paid to the correlation between porous structure and adsorption capacity. The mesopore of NDA-8 played a crucial role during uptake of the DOM. In general, resin in chloride form performed a higher removal rate of DOC. According to the column adsorption test, total adsorption capacity of NDA-8 was calculated to 52.28 mg DOC/mL wet resin. 0.2 mol/L sodium hydroxide solution could regenerate the adsorbent efficiently.

Two novel polymers (NJ-1 and NJ-2) were synthesized by chemically modified a hypercrosslinked polymer NJ-0 with dimethylamine and trimethylamine, respectively. The comparison of the adsorption properties of the three polymers toward phenol, resorcin and phloroglucin was made. The study focused on the static equilibrium adsorption behaviors and the adsorption thermodynamics. Freundlich equation was found to fit the adsorption results well. The effect of amino groups introduced onto the surface of the resin and the structure of phenolic compounds on the adsorption were also studied. The hydrogen-bonding interaction and electrostatic interaction could happen between the amino groups and the adsorbates. The adsorption impetus increased as quantity of hydroxyl groups increased, but the adsorption capacity decreased due to the drop of the matching degree of the aperture of resins and the diameter of adsorbate molecules.

The adsorption properties towards 2,4-dichlorophenol of several adsorption resins, viz. ZH-01, ZH-02 and ZH-03 respectively modified with different functional groups, and of granular activated carbon (GAC) have been compared experimentally with those of Amberlite XAD-4. This paper focuses on the static equilibrium adsorption behaviours and the confirmation of chemisorption characteristics. An equation relating the amount chemisorbed and the assumed chemisorption equilibrium concentration of adsorbate in the aqueous solution was established. This shows that the data may be fitted perfectly by the Langmuir equation. The adsorption capacities measured at different temperatures and the static desorption efficiency reveal that the adsorption of 2,4-dichlorophenol from water onto ZH-01, ZH-02, ZH-03 or GAC occurs via a simultaneous process involving physical adsorption and chemical reaction.

A non-ionic polymer adsorbent (NPA) and its aminated polymeric adsorbent (APA) were prepared and characterized towards adsorption from aqueous solution. Two adsorbates, Reactive Brilliant Blue XBR and 2,4-diaminobenzene sulphonic acid (ABSA), were chosen as adsorbates for competitive adsorption from single-solute solution and binary-solute systems onto the two adsorbents prepared. The results showed that APA, the polymer obtained after amination, exhibited a higher adsorption capacity than NPA towards XBR from the single-solute solution. However, in binary-solute solution adsorption, the presence of ABSA reduced the adsorption capacity towards XBR due to direct competition between XBR and ABSA for the same adsorption sites. This resulted in similar adsorption capacities towards XBR for NPA and APA. Moreover, the adsorption selectivity coefficients obtained for XBR onto ABSA in simultaneous adsorption tests suggested that NPA exhibited more favourable adsorption properties towards the adsorption of XBR from binary-solute systems than APA.

A comparison was made of the adsorption properties towards o-phthalic acid of ND100 resin modified by oxygen groups and ND900 resin modified by amine groups. The work presented focused on various properties including adsorption under static equilibrium conditions, the adsorption thermodynamics and kinetics. In addition, a method was devised for the separation of o-phthalic acid from maleic acid and fumaric acid in wastewater. Two isotherm models (Langmuir and Freundlich) were used to fit the static adsorption results. Both equations fitted the experimental data perfectly. The kinetic results led to the conclusion that the adsorption of o-phthalic acid onto ND900 involved a type of chemical transition.

A new hypercrosslinked polymeric adsorbent (ZH-01) for the adsorption and removal of phenolic compounds from their aqueous solutions was prepared. Batch kinetic studies and comparisons in adsorption capacities between XAD-4, AM-1 and ZH-01 for 800 mg/l phenol were performed, indicating the advantages of ZH-01 for adsorbing phenol, p -cresol and p -nitrophenol. Both the dynamic and thermodynamic studies concluded that the adsorption of phenol and p -cresol onto ZH-01 involved chemisorption while p -nitrophenol was adsorbed physically onto ZH-01. The latter process demonstrated the homogeneous nature of the surface of ZH-01 adsorbent. Mini-column adsorption studies for phenol on ZH-01 showed that its breakthrough capacity and total capacity were 2.38 mmol/g and 3.05 mmol/g, respectively. Methanol exhibited an excellent performance in desorbing phenol from ZH-01.

Adsorption of seven phenols, one aromatic carboxylic acid and one sulfonated aromatic acid from aqueous solution, by a hypercrosslinked polymeric adsorbent (CHA-111) and the derivative animated by dimethylamine was compared. The results of different adsorption isotherms indicated that amino group on the polymeric matrix played a significant role on adsorption of almost all the employed compounds. For most employed compounds adsorption capacities increase to different degree and significantly for those with lower value of pK(a). It may be attributed to the enhanced adsorbent-adsorbate interaction for amino group introduced on the polymeric matrix. The empirical Freundlich isotherm equation was employed to interpret the adsorbent-adsorbate interaction. The adsorption enthalpy change indicated the uptake of phenols on MCH-111 to be an enhanced physical adsorption because of the hydrogen-bonding interaction. Adsorption kinetic study of phenols on CHA-111 and MCH-111 was also conducted and amino group on the matrix will reduce the adsorption rate for change of pore size distribution and loss of macroprous volume as well as the hydration effect on the surface partly.

A community-based intervention trial was carried out to evaluate the effectiveness of alphamethrin-impregnated bed nets for control of Plasmodium vivax malaria and its vector in an area of moderate endemicity in southern Henan province, central China in 1990. Malaria incidence was significantly lower in the intervention group than in the comparison group (2.03 vs. 3.57 per 100 person-years at risk). The protective efficacy for malaria incidence was 43%. The prevalence of malaria parasitaemia among children under 10 years old in the intervention group was about one-quarter of that in the comparison group (0.93% vs. 3.25% and 0.71% vs. 1.96% after one and 4 months use of impregnated nets, respectively). Alphamethrin-impregnated bed nets had a mass killing effect on vector mosquitoes. The outdoor person-biting density of Anopheles anthropophagus and A. sinensis decreased by 70.3% and 29.3% respectively. The density of these 2 mosquito species found resting inside treated nets was close to zero. No side effect was found among users of impregnated bed nets. Impregnation with alphamethrin was more effective on polyester than on cotton netting and residual effects lasted at least one year. Use of alphamethrin is less expensive than permethrin and deltamethrin.